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Bipolar
Disorder: General
Misdiagnosis of bipolar disorder is high (Hirschfeld et
al., J Clin Psychiatry (2003): Perceptions
and impact of bipolar disorder: how far have we really come?
Results of the national depressive and manic-depressive
association 2000 survey of individuals with bipolar disorder),
and clinically accurate early diagnosis is complicated by
the fact that patients often present in the depressive phase,
which can easily be mistaken for unipolar depression. Bipolar
depression, compared with unipolar depression, is more likely
to be associated with hypersomnia, motor retardation, mood
lability, early onset, and a family history of bipolar disorder.
Furthermore, most therapy appropriate for unipolar depression
using traditional antidepressants can increase the risk
of manic switch or cycle acceleration in bipolar disorder,
especially in those with a family history of bipolarity
and suicide: see Bowden (Expert Opin Investig Drugs (2001):
Novel
treatments for bipolar disorder), Bowden
(J Affect Disord (2005): A
different depression: clinical distinctions between bipolar
and unipolar depression), and McIntyre et
al. (Can Fam Physician (2004): Treating
Bipolar Disorder). In addition, most
currently available mood stabilizers, though effective in
managing mania, do not effectively resolve depression.
The paper of N. Kaye (J Am Board Fam Pract (2005): Is
Your Depressed Patient Bipolar?) has invaluably
clarified the key errors in clinical practice involved in
misdiagnosing bipolar depression as unipolar depression,
providing critical clinical guidance as to how to distinguish
between the two entities. In short Kaye notes that bipolar
disorders can be seen as exhibiting three distinct phases:
the depressed phase,
which mimics the clinical picture of major depression (lower
pole), the manic or hypomanic phase
(upper pole), and euthymia,
or the asymptomatic phase. Manic and hypomanic episodes
are characterized by grandiosity, inflated self-esteem,
diminished need for sleep, increased goal-directed activity,
and talkativeness. Then mania and hypomania are themselves
distinguished by the fact that mania is typically of longer
duration, causes more functional impairment, and may be
associated with psychotic features (patients sometimes present
with mixed episodes, in which patients experience both manic
and depressive symptoms, with associated severe functional
impairment).
Under current DSM-IV-TR criteria, only one lifetime manic
or mixed episode is required for a diagnosis of bipolar
I disorder; while the manual specifies that at least one
hypomanic and one depressive episode occur in the absence
of manic or mixed episodes for a diagnosis of bipolar II
disorder.
Diagnosing Bipolar Disorder
In addition, the one-page five-minute MDQ (Mood Disorder
Questionnaire), developed by Dr. Robert M.A. Hirschfeld
(Hirschfeld et al., Am J Psychiatry (2000): Development
and Validation of a Screening Instrument for Bipolar Spectrum
Disorder: The Mood Disorder Questionnaire),
is a brief standardized screening instrument consisting
of 13 yes/no queries + two questions concerning the function
and timing of symptoms; a validation study found that an
MDQ screening score of 7 or more items yields good sensitivity
(at 73%) and very good specificity (at 90%). Isometsä
et al. (BMC Psychiatry (2003): The
Mood Disorder Questionnaire improves recognition of bipolar
disorder in psychiatric care) found the MDQ
to be a feasible screen for bipolar disorder. See also Das
et al. (JAMA (2005): Screening
for Bipolar Disorder in a Primary Care Practice)
and Hirschfeld (J. Am. Board Fam. Pract (2005): Screening
for Bipolar Disorder in Patients Treated for Depression
in a Family Medicine Clinic). The MDQ is
available online from numerous sources (see for example:
BipolarHelpCenter:
Mood Disorder Questionnaire;
also downloadable as pdf: MDQ
PDF).
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Forms of Bipolar
Disorder
Three distinct major forms of bipolar disorder are currently
recognized, summarized below. See Morehead Well-Connected
Report (2004): Bipolar
Disorder; Bipolar Disorder Today: Bipolar
Disorder DSM IV Criteria); Bowden (MedGenMed
(2002): Diagnosis of Bipolar Disorders: Focus
on Bipolar Disorder I and Bipolar Disorder II);
The Merck Manual of Diagnosis and Therapy: Bipolar
Disorder; and DBSA: Bipolar
Disorder for accessible discussions of these
classifications.
Bipolar I Disorder
This is characterized by one or more manic episodes or mixed
episodes (symptoms of both a mania and a depression occurring
nearly every day for at least 1 week) and one or more major
depressive episodes. Bipolar I disorder represents the most
severe form of the illness marked by extreme manic episodes.
Bipolar II Disorder
This is characterized by one or more depressive episodes
accompanied by at least one hypomanic episode. Hypomanic
episodes have symptoms similar to manic episodes but are
less severe, but must be clearly different from a person’s
non-depressed mood. For some, hypomanic episodes are not
severe enough to cause notable problems in social activities
or work. However, for others, they can be both troublesome
and disruptive. Bipolar II disorder may be misdiagnosed
as depression he signs of hypomania are missed. In a recent
DBSA
(Depression and Bipolar Support Alliance) survey, nearly
seven out of ten people with bipolar disorder had been misdiagnosed
at least once. Sixty percent of those people had been diagnosed
with depression.
Cyclothymic Disorder
This disorder is characterized by chronic fluctuating moods
involving periods of hypomania and depression. The periods
of both depressive and hypomanic symptoms are shorter, less
severe, and do not occur with regularity as experienced
with bipolar II or I. However, these mood swings can impair
social interactions and work. Many, but not all, people
with cyclothymia develop a more severe form of bipolar illness.
Agitated Depression
Although not an official classification, Maj et al. (Am
J Psychiatry (2003): Agitated
Depression in Bipolar I Disorder: Prevalence, Phenomenology,
and Outcome) have sought to delineate another
potential category or subcategory of bipolar disorder, which
they refer to as agitated depression in Bipolar I Disorder:
as they note, patients with agitated depression were consistently
not elated or grandiose, but one-fourth had the cluster
of symptoms with racing thoughts, pressured speech, and
increased motor activity, and one-fourth had the paranoia-aggression-irritability
cluster; see also the commentary of Sato et al. (Am J Psychiatry
(2003): Evidence
of Depressive Mixed States).
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Lamotrigine
Lamotrigine has shown activity in
bipolar depression and has a very low risk of manic switch.
Lamotrigine has demonstrated efficacy in both acute bipolar
depression and maintenance efficacy in rapid cycling bipolar
patients, especially those patients with bipolar II disorder
(principally manifested as depression). Two placebo-controlled
trials demonstrated the efficacy of lamotrigine in acute
bipolar depression. Calabrese et al. (J Clin Psychiatry
(1999): A
double-blind placebo-controlled study of lamotrigine monotherapy
in outpatients with bipolar I depression)
found lamotrigine, 50 mg/day and 200 mg/day, significantly
more efficacious than placebo in reduction of depressive
symptoms in patients with bipolar I depression in a 7-week
trial, with a trend for greater efficacy of 200 mg/day over
50 mg/day, There were no significant differences in switch
rates between the treatment groups. Frye et al. (J Clin
Psychopharmacol (2000): A
placebo-controlled study of lamotrigine and gabapentin monotherapy
in refractory mood disorders) compared lamotrigine,
gabapentin, and placebo in a crossover study in patients
with treatment-refractory rapid-cycling bipolar I and II
disorders. Among the 3 treatment groups, only lamotrigine
was associated with significant reductions in depressive
symptoms.
More recently, Goodwin et al. (J Clin Psychiatry (2004):
A
pooled analysis of 2 placebo-controlled 18-month trials
of lamotrigine and lithium maintenance in bipolar I disorder)
analyzed two clinical trials, prospectively designed for
combined analysis, compared placebo, lithium, and lamotrigine
for treatment of bipolar I disorder in recently depressed
or manic patients, confirming the earlier findings that
lamotrigine and lithium stabilized mood by delaying the
time to treatment for a mood episode. Lamotrigine was effective
against depression and mania, with more robust activity
against depression. Lithium was effective against mania.
And Manning et al. (J Affect Disord (2005): Sustained
remission with lamotrigine augmentation or monotherapy in
female resistant depressives with mixed cyclothymic-dysthymic
temperament) found that lamotrigine induced
prolonged illness remissions in a substantial number of
female patients whose symptoms were both complex and refractory,
most of whom manifested cyclothymic and depressive temperaments,
and were refractory to multiple antidepressant and antidepressant/mood
stabilizer combinations, before remitting with lamotrigine
augmentation or monotherapy.
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Other
Monotherapy:
As demonstrated by Bauer & Mitchner (Am J Psychiatry
(2004): What
Is a "Mood Stabilizer"? An Evidence-Based Response)
lithium, valproate, and olanzapine had unequivocal evidence
for efficacy in acute manic episodes, lithium in acute depressive
episodes and in prophylaxis of mania and depression, and
lamotrigine in prophylaxis (relapse polarity unspecified).
Furthermore, Gijsman et al. (Am J Psychiatry (2004): Antidepressants
for Bipolar Depression: A Systematic Review of Randomized,
Controlled Trials) reviewed the literature
and found, against the widespread concerns of antidepressant-induced
switching, that antidepressants are effective in the short-term
treatment of bipolar depression and that the trial data
do not suggest that switching is a common early complication
of such treatment.
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Older
Anticonvulsants
Although early anticonvulsants divalproex and carbamazepine
are still prescribed for bipolar disorders, side effects
profiles are limiting (see Goldberg & Citrome, Postgrad
Med (2005): Latest
therapies for bipolar disorder. Looking beyond lithium):
with divalproex, these may be nausea, sedation, weight gain,
alopecia, and thrombocytopenia, necessitating frequent liver
function monitoring, while with carbamazepine, the main
concern is induction of metabolism of that agent and of
many other agents, necessitating dose adjustments for all
affected medications, with adverse effects including sedation
and a small risk of liver toxicity and agranulocytosis (the
keto analogue of carbamazepine, oxcarbazepine, has shown
possible pharmacodynamic efficacy in bipolar disorder, but
RCT evidence for efficacy is not to date available).
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Second-generation
Antipsychotics
Currently, five second-generation antipsychotics have received
FDA approval for monotherapy in acute bipolar mania: olanzapine
(Zyprexa), risperidone (Risperdal),
quetiapine (Seroquel), ziprasidone
(Geodon), and aripiprazole
(Abilify), with olanzapine, risperidone, quetiapine also
approved indications for add-on therapy, and olanzapine
in addition approval for maintenance therapy. These atypical
agents (olanzapine, risperidone and quetiapine) have demonstrated
efficacy against the manic phase of bipolar disorder and
appear also to have potential in the depressive phase. Quetiapine
appears to also be efficacious as monotherapy in acute bipolar
depression (Calabrese et al., Am J Psychiatry (2005): A
Randomized, Double-Blind, Placebo-Controlled Trial of Quetiapine
in the Treatment of Bipolar I or II Depression),
including suicidal thoughts, anxiety, sleep quality and
global quality of life (Keck, Bipolar Disord (2005):
Bipolar depression: a new role
for atypical antipsychotics?). In the review
of Post & Calabrese (Expert Rev Neurother (2004):
Bipolar depression: the role of
atypical antipsychotics), olanzapine monotherapy
significantly improved depressive symptoms compared with
placebo in an 8-week RCT clinical study, but the magnitude
of the clinical effect was small, although the observed
improvement in depressive symptoms became moderately large
when olanzapine was combined with fluoxetine (Prozac). in
another 8-week RCT clinical study, quetiapine monotherapy
also resulted in significant improvements compared with
placebo in patients with either bipolar I or II disorder,
but in this case the effect size was large. Finally, a 6-month
open-label study of risperidone added to ongoing therapy
demonstrated improvements in depressive symptoms in patients
with bipolar and schizoaffective disorders experiencing
a manic, hypomanic, mixed or depressive episode.
Gao & Calabrese (Bipolar Disord (2005): Newer
treatment studies for bipolar depression)
found that lamotrigine only significantly reduced core symptoms
of depression compared with placebo, and that olanzapine,
olanzapinefluoxetine combination (OFC), and quetiapine
are effective in the acute treatment of bipolar depression,
and lamotrigine is more effective in preventing bipolar
depression compared with lithium and divalproex.
In addition, GAO and Calabrese (above) found both pramipexole
(Mirapex), a dopamine D2/D3 receptor agonist, and omega-3
fatty acids augmentation to a mood stabilizer had superiority
to placebo in reducing depressive symptoms (on the efficacy
of pramipexole as an antidepressant in bipolar disorder,
see also Goldberg et al., Am J Psychiatry (2004): Preliminary
Randomized, Double-Blind, Placebo-Controlled Trial of Pramipexole
Added to Mood Stabilizers for Treatment-Resistant Bipolar
Depression). They found topiramate
(Topamax) augmentation of an mood stabilizer was equally
as effective as bupropion-SR.
GAO& Calabrese (above) further found that patients treated
with a mood stabilizer responded well to the addition of
agomelatine (Valdoxan), a melatonin
receptor agonist with 5-HT2C antagonist properties. However,
the study found that inositol and repetitive transcranial
magnetic stimulation were not superior to placebo. Finally,
lamotrigine and olanzapine, and to a lesser extent, divalproex,
are superior to placebo in preventing depressive relapses.
All agents were relatively well tolerated.
Evidencewatch Warning:
Anticonvulsants and Cognitive Impairment
However Evidencewatch notes that that cognitive impairment
may be a concern with both topiramate and lamotrigine. In
their review of the cognitive effects of anticonvulsant
drugs, Aldenkamp et al. (Epilepsia (2003): Newer
Antiepileptic Drugs and Cognitive Issues)
concluded that clear clinical evidence for topiramate-induced
cognitive impairment, especially for verbal memory parameters
such as verbal IQ, verbal fluency, and verbal learning,
with some somnolence, psychomotor slowing, speech disorders,
and concentration and memory difficulties for escalating
the topiramate dose to 200 or 400 mg/day. Kockelmann et
al. (Epilepsy Behav (2004): Cognitive
profile of topiramate as compared with lamotrigine in epilepsy
patients on antiepileptic drug polytherapy: relationships
to blood serum levels and comedication) also
found that patients on topiramate exhibit a cognitive pattern
with specific impairment in executive functions (phonematic
verbal fluency, memory spans, and working memory). This
contrasts sharply with monotherapy and adjunctive therapy
with lamotrigine which was associated with improved cognitive
functioning and reduced neurocognitive side effects (see
Aldenkamp et al., Epilepsy Behav (2001): A
Systematic Review of the Effects of Lamotrigine on Cognitive
Function and Quality of Life); also Ginsberg
et al. J Clin Psychiatry (2004): Effect
of lamotrigine on cognitive complaints in patients with
bipolar I disorder),
Olanzapine-Fluoxetine
In 2003, Symbyax, a combination
of olanzapine and the SSRI antidepressant fluoxetine, became
the first combination therapy approved by the FDA for treatment
of acute bipolar depression. Tohen et al. (Arch Gen Psychiatry
(2003): Efficacy
of Olanzapine and Olanzapine-Fluoxetine Combination in the
Treatment of Bipolar I Depression) found
combined olanzapine-fluoxetine to be more effective than
olanzapine and placebo in the treatment of bipolar I depression
without increased risk of developing manic symptoms.
Efficacy of Second-generation Antipsychotics
Evidence of efficacy has been sufficiently demonstrated
across numerous well-controlled studies that the American
Psychiatric Association advises the integration of second-generation
antipsychotics with lithium or certain anticonvulsant medications
at the outset of therapy for severe forms of acute mania,
and further advises ongoing use of second-generation antipsychotics
as required to prevent recurrence (Amer Psychiatric Assoc:
Practice Guideline for the Treatment
of of Patients with Bipolar Disorder (Second Edition)).
Illness subtypes for which second-generation antipsychotics
may have distinct value, including (1) prior lack of response
to lithium or anticonvulsant drugs, (2) mixed mania, (3)
rapid cycling, (4) substance abuse or other psychiatric
comorbidities, (5) bipolar depression, and (6) psychotic
manias.
The available evidence suggests both short- and long-term
comparabilities in efficacy of the various antipsychotics
in bipolar disorder, although olanzapine may be superior
to lithium for mania relapse prevention).
Adverse Events:
Second-Generation Antipsychotics
With respect to adverse events, the FDA requires a warning
about hyperglycemia and diabetes in the product labeling
of these second-generation antipsychotics, with more concern
associated with olanzapine, quetiapine, and risperidone
(Risperdal) than for ziprasidone or aripiprazole. Warnings
about tardive dyskinesia and neuroleptic malignant syndrome
remain; however, the risk of these events is substantially
less than for first-generation antipsychotics and is likely
related to a much lower propensity for second-generation
antipsychotics to cause extrapyramidal symptoms.
Evidencewatch Commentary:
However, despite the FDA-required warning concerning the
association of antipsychotic agents and diabetes, Bushe
& Leonard in their recent critical review (Br J Psychiatry
Suppl (2004): Association
between atypical antipsychotic agents and type 2 diabetes:
review of prospective clinical data) of diabetogenic
risk between antipsychotic medications this issue noted
that the claimed association is largely based on retrospective
studies not controlled for important confounders; their
review found (1) no difference in the incidence of glycemic
abnormalities between placebo cohorts and antipsychotic
medication cohorts; (2) no significant difference between
any of the antipsychotic medications studied in terms of
their association with glycemic abnormalities; and that
(3) treatment-related weight gain did not appear to increase
the risk of developing diabetes.
Adverse Events:
Antidepressants for Bipolar Depression
There are numerous cautions in the literature against the
induction of (hypo)mania consequent to the use of antidepressants
in bipolar disorder. However, the recent critical review
of Visser (World J Biol Psychiatry (2005): Bipolar
disorder, antidepressants and induction of hypomania or
mania. A systematic review) found no strong
evidence that use of antidepressants in bipolar disorder
increases the risk of (hypo)mania.
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Combination Therapy:
Given that bipolar disorder patients frequently don't respond
sufficiently to treatment with a single mood stabilizer,
psychiatrists frequently employ combination therapy and
add
(1) antipsychotics,
(2) antiepileptics, or
(3) antidepressants
to mood stabilizers. Evidence suggests that such combination
therapy can be more effective than monotherapy in controlling
breakthrough or treatment-resistant episodes.
Thus, atypical antipsychotics have been shown to be effective
adjunctive treatments for mania and for patients with psychotic
symptoms during a depressive episode, while the combination
of a mood stabilizer and the antiepileptic lamotrigine or
an antidepressant has been found to control bipolar depression,
with lamotrigine therapy being especially useful as maintenance
treatment of bipolar I disorder; see Bowden (J Clin Psychiatry
(2004: Making
optimal use of combination pharmacotherapy in bipolar disorder)
who notes in this connection that the APA (American Psychiatric
Association) guideline for the treatment of bipolar disorder
recommends optimizing individual medications before switching
to combination therapy. The clinical challenge is selecting
a combination treatment regimen with an acceptable side
effect profile given the propensity for patients to discontinue
therapy they cannot tolerate. Careful and continued monitoring
of adverse effects is critical.
In addition, also FDA-approved for the treatment of depression
and depressive episodes in bipolar disorder is a combination
of olanzapine and fluoxetine. And as noted by Bowden (J
Clin Psychiatry (2005): Treatment
Options for Bipolar Depression) psychoeducation
has also been examined as a possible treatment for depression
in bipolar disorder, and a study has shown that patients
receiving psychoeducation plus medication may have a lower
rate of relapse than patients who receive medication alone.
Other effective combination regimens for which RCT studies
provide good evidence (Bowden (Expert
Opin Investig Drugs (2001): Novel
treatments for bipolar disorder)
are risperidone or olanzapine in combination with lithium
or valproate; these yield greater improvement in acute mania
than the mood stabilizers alone. Similarly, valproate combined
with antipsychotics provided greater improvement in mania
than antipsychotic medication alone and resulted in lower
dosage of the antipsychotic medication; see also Medscape
(2004): Stabilizing
Depression in Bipolar Disorder), especially
the contributions of Herman: Lamotrigine:
A Depression Mood Stabilizer and Calabrese:
Depression Mood Stabilization:
Novel Concepts and Clinical Management.
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Maintenance
Therapies
Muzina and Calabrese (Aust N Z J Psychiatry (2005): Maintenance
therapies in bipolar disorder: focus on randomized controlled
trials) have completed a systematic review
of RCTs on bipolar disorder :maintenance therapies, finding
that:
(1) Lithium is a highly effective
prophylactic antimanic agent and remains the gold standard
for overall preventative efficacy in bipolar disorder, especially
in decreasing manic and hypomanic relapses, while possessing
possess the greatest antidepressant effect. Cipriani et
al (Am J Psychiatry (2005): Lithium
in the Prevention of Suicidal Behavior and All-Cause Mortality
in Patients With Mood Disorders: A Systematic Review of
Randomized Trials) found lithium to be effective
in the prevention of suicide, deliberate self-harm, and
death from all causes in patients with mood disorders (in
bipolar disorder and unipolar depression, schizoaffective
disorder, dysthymia, and rapid cycling).
And in seeking to resolve discrepancies in lithium studies,
Severus et al. (J Clin Psychopharmacol (2005): Is
the prophylactic antidepressant efficacy of lithium in bipolar
I disorder dependent on study design and lithium level?)
have found that lithium's efficacy against manic relapse/recurrence
is robust at plasma levels between 0.8 and 1.2 mmol/L, whereas
lithium's efficacy against depressive relapse/recurrence
may be more modest and dependent on whether a response during
the preceding acute episode was achieved by lithium treatment,
and that furthermore, it might be advisable to continue
lithium without interruption at the same dose/plasma level,
which yielded the initial response; they observe that a
lithium level between 0.5 and 0.8 mmol/L may be equally
efficacious against overall relapse and associated with
equal or even superior efficacy regarding depressive relapse/recurrence.
However, Deshauer et al. (Bipolar Disord (2005): Re-evaluation
of randomized control trials of lithium monotherapy: a cohort
effect) have quantified the impact of pre-randomization
enrichment designs and diagnostic drift on randomized controlled
trials (RCTs) of lithium maintenance therapy, and given
that lithium maintenance RCTs differ in patient selection,
design, and outcome, suggesting a potential cohort effect
associated with the use of pre-randomization enrichment
phases and, to a lesser extent, with diagnostic drift.
Adverse Effects: Lithium has numerous side effects,
a narrow therapeutic index, and carries the risk of fatal
overdose (see PDRhealth: Eskalith
(Lithium Carbonate)).
(2) The anticonvulsant Divalproex
(Depakote) may also prevent recurrent bipolar mood episodes
(see, among others, the randomized, double-blind, parallel-group,
multicenter study of Gyulai et al, Neuropsychopharmacology
(2004): Maintenance
Efficacy of Divalproex in the Prevention of Bipolar Depression
who found that divalproex improved several dimensions of
depressive morbidity and reduced the probability of depressive
relapse in bipolar disorder), but there is nonetheless only
a relative small number of controlled maintenance studies
to make this conclusion more definitive.
Adverse Effects: Divalproex is associated with weight
gain, tremor, hepatotoxicity, and many drug-drug interactions
(see PDRhealth: Depakote
(Divalproex (Valproic Acid)).
(3) Extensive and well-designed research supports the use
of lamotrigine (Lamictal),
another anticonvulsant, in the acute and prophylactic management
of bipolar I disorder. It also offers a spectrum of clinical
effectiveness complementing lithium: it appears to stabilize
mood 'from below baseline' by preventing episodes of depression,
and is also effective in rapid-cycling bipolar II disorder.
Adverse Effects: Although lamotrigine must be carefully
titrated and monitored to avoid the possibility of serious
rash, it does not require blood monitoring and is associated
with minimal weight gain, sexual side effects, sedation,
or cognitive impairment (see PDRhealth: Lamictal
(Lamotrigine)).
(4) Carbamazepine (Tegretol),
still another anticonvulsant, may be a useful alternative
to lithium, divalproex and lamotrigine, especially for patients
with a history of mood-incongruent delusions and other comorbidities,
but the controlled evidence is more equivocal for this agent's
efficacy, and it appears it may lose some of its prophylactic
effect over time.
Adverse Effects: Carbamazepine, which is actually
not FDA-approved for the treatment of bipolar disorders,
has nonetheless been demonstrated in rigorous studies to
be efficacious, but it requires serum level monitoring and
carries a risk of hyponatremia and a low risk of blood dyscrasia
(see PDRhealth: Tegretol
(Carbamazepine)).
(5) Finally, emerging data continue to support the growing
use of atypical antipsychotics, particularly olanzapine
(Zyprexa), as a maintenance therapy for bipolar disorder.
Adverse Effects: Olanzapine, like other atypical
antipsychotics, have been associated with a dysmetabolic
syndrome marked by weight gain, increased risk of
diabetes, and elevated triglycerides, occasionally accompanied
by pancreatitis. Therefore, monitoring of patients is
required when these agents are to be used in the
longer term, in conjunction with the Consensus
Statement on Antipsychotic Medications and Obesity
(ADA/APA/AACE/NAASO (American Diabetes Association/American
Psychiatric Association/ American Association of Clinical
Endocrinologists; North American Association for the Study
of Obesity; published in Diabetes Care (2004): Consensus
Development Conference on Antipsychotic Drugs and Obesity
and Diabetes); and see the response by E.
Barrett to various criticisms and comments on the Consensus
Statement (E. Barrett, Diabetes Care (2004): Consensus
Development Conference on Antipsychotic Drugs and Obesity
and Diabetes
Response to Holt, Citrome and Volevka, Isaac and Isaac,
and Boehm et al.). See also Henderson et
al. (Arch Gen Psychiatry (2005): Glucose
Metabolism in Patients With Schizophrenia Treated With Atypical
Antipsychotic Agents: A Frequently Sampled Intravenous Glucose
Tolerance Test and Minimal Model Analysis)
who found that both nonobese clozapine- and olanzapine-treated
groups displayed significant insulin resistance and impairment
of glucose effectiveness compared with risperidone-treated
subjects; and J. Rosack (Psychiatric News (2004): Antipsychotics
Diabetes Risk Prompts Call for Better Assessment).
However, against this Morris and Mohammed (J Psychopharmacol
(2005): Metabolism,
lifestyle and bipolar affective disorder)
reviewed whether the risk of obesity and related morbidity
and mortality are raised in bipolar disorder, arguing that
reduced exercise and poor diet, frequent depressive episodes
comorbidity with substance misuse and poor quality general
medical care contribute to the additional risk of these
medical problems in people with bipolar depression. They
conclude that there is insufficient evidence of an association
of any any of these factors with specific drug treatments
or that patients with bipolar disorder are intrinsically
more sensitive than other patients to weight gain and medical
problems associated with long-term use of psychotropic medication,
and that in fact long-term treatment of bipolar disorder
with lithium, antipsychotics and tricyclic antidepressants
may reduce overall mortality.
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Major
Depressive Disorder (MDD)
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Types
of Depression:
[MDD = major
depressive disorder]
MDD (major depressive disorder) or unipolar depression
- characterized
by depressed mood, hopelessness, helplessness, intense feelings
of guilt, sadness, low self esteem, thoughts of self harm,
and suicide - is
an important factor in disability worldwide, with up to
15% of MDD patients eventually committing suicide (Davies
et al., BMJ (2001): Depression,
suicide, and the national service framework).
Within MDD (major depressive disorder), it is common to
differentiate entities of recurrent depression, treatment-resistant
depression, chronic depression, atypical depression, and
psychotic depression. Depression may present with
atypical features, the most common being overeating and
oversleeping. The syndrome is also associated with mood
reactivity and a
long-standing pattern of interpersonal rejection and over-sensitivity.
Coexisting diagnoses of panic disorder, substance abuse
and somatisation disorder may
also be common.
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Traditional Antidepressant Drugs:
- TCAs (tricyclic antidepressants)
- SSRIs (selective serotonin
reuptake inhibitors)
- MAOIs (monoamine oxidase
inhibitors)
- Third Generation Antidepressants
including dual mechanism
SNRIs
(Serotonin and Noradrenaline Reuptake Inhibitors)
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TCAs:
TCAs (amitriptyline (Elavil), amoxapine (Asendin), clomipramine
(Anafranil), desipramine (Norpramin), dothiepin hydrochloride
(Prothiaden), doxepin (Adapin, Sinequan), imipramine (Tofranil),
lofepramine (Gamanil, Lomont), nortriptyline (Pamelor),
protriptyline (Vivactil), trimipramine (Surmontil)) have
equal efficacy compared with alternative antidepressants
but are less well tolerated, particularly in outpatients.
With respect to inpatients, there is evidence suggesting
that there is a statistically significant difference favoring
TCAs over alternative antidepressants on reducing depression
symptoms by the end of treatment, but the size of this difference
is unlikely to be of clinical significance. However, there
is strong evidence suggesting that there is a clinically
significant difference favoring alternative antidepressants
over TCAs on reducing the likelihood of leaving treatment
early due to side effects.
Recently, Arroll et al. (Ann Fam Med (2005): Efficacy
and tolerability of tricyclic antidepressants and SSRIs
compared with placebo for treatment of depression in primary
care: a meta-analysis) noted the absence
of systematic reviews of depression treatment comparing
antidepressants with placebo, disallowing concluding efficacy
in primary care; their systematic review is the first comparing
antidepressants with placebo for treatment of depression
in a primary care setting. They found that both TCAs and
SSRIs are effective, and were the first to show that even
low-dose TCAs (100 mg or 75 mg) are effective in primary
care.
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MAOIs:
Monoamine oxidase inhibitors (MAOIs) (Isocarboxazid (Marplan),
Moclobemide (Aurorix, Manerix, Moclodura),
Phenelzine (Nardil), Tranylcypromine (Parnate), Selegiline
(Selegiline, Eldepryl)) exert their therapeutic effect by
binding irreversibly to monoamine oxidase, the enzyme responsible
for the degeneration of monoamine neurotransmitters such
as noradrenaline and serotonin. This results in increased
monoamine neurotransmission.
All MAOIs have the potential to induce hypertensive crisis
if foods containing tyramine (also metabolized by MAO) are
consumed or drugs that increase monoamine neurotransmission
are co-prescribed, so that such foods and drugs must be
avoided for at least 14 days after discontinuing MAOIs.
In sum, such dietary restrictions, coupled with potentially
serious drug interactions, and the availability of safer
classes of antidepressants have led to these irreversible
MAOIs being infrequently prescribed. Nonetheless, MAOIs
are still widely cited as being the most effective antidepressants
for the treatment of atypical depression for achieving remission
and response, although the latest evidence suggests this
to be true largely in a clinical advantage of one MAOI agent,
phenelzine, over TCAs; thus it is relevant to note the findings
of NICE (2004): Depression:
Management of Depression in Primary and Secondary Care
[National Clinical Practice Guideline Number 23 (15 Dec
2004)] and the MHRA (2005): Safety
of Selective Serotonin Reuptake Inhibitor Antidepressants
[Letter to Healthcare Professionals (18 Feb 2005)] that
compared with SSRIs (especially fluoxetine), there is evidence
of no difference on mean endpoint scores, and insufficient
evidence on other outcome measures.
-
SSRIs
The Major SSRIs
Citalopram (Celexa)
Escitalopram (Lexapro)
Fluoxetine (Prozac, Sarafem)
Fluvoxamine (Luvox)
Paroxetine (Paxil, Paxil CR)
Sertraline (Zoloft)
The selective serotonin reuptake inhibitors (SSRIs) inhibit
the reuptake of serotonin into the presynaptic neurone thus
increasing neurotransmission. Although they selectively
inhibit serotonin reuptake, they are not serotonin specific:
some of the drugs in this class also inhibit the reuptake
of noradrenaline and/or dopamine to a lesser extent.
As a class, they are associated with fewer anticholinergic
side effects and are less likely to cause postural hypotension
or sedation. Dosage titration is not routinely required
so subtherapeutic doses are less likely to be prescribed.
They are also less cardiotoxic and much safer in overdose
than TCAs or MAOIs. Tata et al. (Heart (2005): General
population based study of the impact of tricyclic and selective
serotonin reuptake inhibitor antidepressants on the risk
of acute myocardial infarction) concluded
that although antidepressant prescriptions are associated
with an increased risk of MI, (1) the size of these effects
is similar for TCA and SSRI exposures, and (2) that nonetheless,
the lack of specificity between types of antidepressants
and the lower risks found in the self controlled analysis
suggest that these associations are more likely due to factors
relating to underlying depression and health services utilization
than to specific adverse drug effects. Given these advantages,
SSRIs are in widespread use as better tolerated first-line
antidepressants.
The most problematic side effects of this class of drugs
are nausea, diarrhea and headache. Fluvoxamine, fluoxetine
and paroxetine are potent inhibitors
of various hepatic cytochrome metabolizing enzymes
precipitating many significant drug interactions. Sertraline
is less problematic in this connection, although enzyme
inhibition is dose-related, with citalopram being relatively
safe in this regard. All told, the SSRI group has the advantage
of ease of dosing and low toxicity in overdose, with better
tolerability than TCAs. SSRIs are also safer than TCAs in
overdose.
Common adverse effects include GI upset (nausea and diarrhea),
central nervous system effects (dizziness, agitation, insomnia,
and tremor), male and female sexual dysfunction (erectile,
desire, orgasm, ejaculation, satisfaction, vaginal lubrication),
and changes in energy level (i.e., fatigue, restlessness).
Extrapyramidal symptoms are relatively rare and seem to
be most common with paroxetine. [For more information on
SSRI-induced sexual dysfunction, see our discussion Antidepressants
and SD (sidebar).]
SSRIs may also increase the risk of upper gastrointestinal
bleeding, probably by altering platelet function. This risk
seems to be increased in people who are also taking low-dosage
aspirin or nonsteroidal anti-inflammatory drugs, who have
a history of gastrointestinal bleeding, or who are elderly
(van Walraven et al., BMJ (2001): Inhibition
of serotonin reuptake by antidepressants and upper gastrointestinal
bleeding in elderly patients: retrospective cohort study);
Meijet et al., Arch Intern Med (2004): Association
of Risk of Abnormal Bleeding With Degree of Serotonin Reuptake
Inhibition by Antidepressants ). Unpublished
and reported findings have also raised concern about the
potential for an increase in incidence gastrointestinal
bleeding and bleeding from other sites (P. Padhan, Annlas
Online (2005): Newer
Antidepressants and Risk of Bleeding).
Although overall there is little compelling evidence to
suggest an efficacy advantage of any one SSRI over another.
For escitalopram (Lexapro) - the most serotonin selective
SSRI and a racemic mixture of two forms of citalopram (Celexa),
the s-citalopram and r-citalopram - there is evidence suggesting
that there is a statistically significant difference favoring
escitalopram over other antidepressants on (1) increasing
the likelihood of patients achieving a 50% reduction in
depression symptoms, (2) reducing depression symptoms, although
the size of these differences is unlikely to be of clinical
significance. However, there is evidence to suggest that
there is no clinically significant difference between escitalopram
and other antidepressants on increasing the likelihood of
patients achieving remission (NICE and MHRA studies, cited
above). Nonetheless, differences in the clinical profiles
of these agents may be leveraged in choosing the optimal
therapy for individual patients or classes of patients (see
Anderson & Edwards, Advances in Psychiatric Treatment
(2001):
Guidelines for Choice of Selective
Serotonin Reuptake Inhibitor in Depressive Illness;
see especially their tables Distinguishing
features of individual selective serotonin reuptake inhibitors
(SSRIs) , and Guidelines
for choosing an individual selective serotonin reuptake
inhibitor (SSRI)).
These findings are in essential agreement with those of
Hansen et al. (Ann Intern Med (2005): Efficacy
and safety of second-generation antidepressants in the treatment
of major depressive disorder) who also concluded
that overall, second-generation antidepressants probably
do not differ substantially for treatment of major depressive
disorder, and that therefore the choice of an agent that
is most appropriate for a given patient is a clinically
difficult problem. Meta-analyses did show a modest but statistically
significant additional treatment effect for sertraline (Zoloft)
and venlafaxine (Effexor) compared with fluoxetine (Prozac,
Sarafem). These researchers noted the methodological problems:
(1) fully about 96% of comparative trials were sponsored
by or had at least 1 author affiliated with a pharmaceutical
company, with the remaining trials not reporting funding
sources, thus raising the potential for publication bias;
(2) adverse event profiles differed among drugs, but the
degree and quality of adverse event assessment varied, and
only 13% of trials used a standardized scale to assess adverse
events.
In sum, SSRIs are relatively well-tolerated drugs with efficacy
comparable to alternative antidepressants, and may be particularly
suitable for (1) women who may respond preferentially to
SSRIs and (2) for those with suicidal intent, due to their
safety in overdose.
-
SSRIs and OCD
SSRIs are well established in the treatment of obsessive-compulsive
disorder (OCD), both in its adult and pediatric forms (Grist
et al, CNS Spectr (2003): WCA
recommendations for the long-term treatment of obsessive-compulsive
disorder in adults). The pharmacological
treatment of OCD includes the tricyclic antidepressant clomipramine
and the SSRIs, and although all SSRIs have shown benefit
in acute treatment trials, fluvoxamine, fluoxetine, and
sertraline have also demonstrated benefit in long-term treatment
trials of at least 24 weeks (note: only clomipramine, sertraline,
and fluvoxamine are FDA-approved for use in children and
adolescents). Treatment guidelines recommend first-line
use of an SSRI over clomipramine, given clomipramine's less
favorable adverse-event profile, with pharmacotherapy being
sustained for a minimum of 1-2 years before considering
very gradual withdrawal.
In addition, some third generation so-called dual mechanism
drugs such as mirtazapine (Koran et al. J Clin Psychiatry
(2005): Mirtazapine
for obsessive-compulsive disorder: an open trial followed
by double-blind discontinuation) appear to
also be of benefit in OCD treatment; mirtazapine can also
be used as part of an augmentation strategy in OCD therapy:
Pallanti et al. (J Clin Psychiatry (2004): Response
acceleration with mirtazapine augmentation of citalopram
in obsessive-compulsive disorder patients without comorbid
depression: a pilot study) found earlier
onset of response action in OCD symptoms and reduced undesired
side effects when mirtazapine was added to citalopram. And
March et al. (J Child Adolesc Psychopharmacol (2006): Treatment
Benefit and the Risk of Suicidality in Multicenter, Randomized,
Controlled Trials of Sertraline in Children and Adolescents)
reviewed the balance between the benefits of treatment and
the risk of suicidality in children and adolescents in multicenter,
randomized, controlled trials of sertraline (Zoloft) versus
placebo, finding a positive benefit-to-risk ratio for sertraline
in adolescents with MDD and in patients of all ages with
OCD.
Finally, as noted by S. Aronson (eMedicine (2004) : Obsessive-Compulsive
Disorder) the dual mechanism agents venlafaxine
(Effexor) and duloxetine (Cymbalta) hypothetically also
have efficacy in OCD, with safety and tolerability profiles
comparable to those of the SSRIs, although neither is currently
FDA-approved specifically for OCD treatment.
Bupropion (Wellbutrin, Zyban)
Bupropion is a weak reuptake
inhibitor for norepinephrine
and dopamine. Although originally launched as an antidepressant,
it has been recently redirected as an aid for smoking cessation
and obesity control. In addition, it appears that it can
be used in the prevention of the onset of autumn-winter
depression: it's possible to prevent recurrence of seasonal
major depressive episodes by beginning bupropion treatment
early in the season before the onset of SAD (Seasonal affective
disorder) symptomology (Modell et al., Biol Psychiatry (2005):
Seasonal Affective Disorder and
Its Prevention by Anticipatory Treatment with Bupropion
XL).
The balance of the evidence suggests that bupropion and
the SSRIs are equivalently effective in the treatment of
depression, with sexual dysfunction commonly presenting
as a complication of SSRI therapy, whereas treatment with
bupropion induced no more sexual dysfunction than placebo
(Thase et al., Clin Psychiatry (2005): Remission
rates following antidepressant therapy with bupropion or
selective serotonin reuptake inhibitors: a meta-analysis
of original data from 7 randomized controlled trials).
Furthermore, bupropion is less likely than other antidepressants
to cause weight gain and sexual dysfunction, known to be
the two side effects that are of greatest concern to patients
and with the greatest impact on long-term compliance (Zimmerman
et al., J Clin Psychiatry (2005): Why
isn't bupropion the most frequently prescribed antidepressant?
).
-
Third Generation
/ Dual Mechanism Agents:
There is evidence suggesting that there is a statistically
significant difference favoring third-generation antidepressants
(mirtazapine, venlafaxine, reboxetine (UK only)) over SSRIs
on reducing depression symptoms, but the size of this difference
is unlikely to be of clinical significance (NICE (2004):
Depression:
Management of Depression in Primary and Secondary Care
[National Clinical Practice Guideline Number 23 (15 DEC
2004)]); also MHRA (2005): Safety
of Selective Serotonin Reuptake Inhibitor Antidepressants
[Letter to Healthcare Professionals (18 Feb 2005)]).
Mitrazapine (Remeron)
Mirtazapine is a noradrenaline and specific serotonin antidepressant
(NaSSA) which blocks presynaptic alpha 2 receptors on both
NA and 5HT neurones, and which also blocks postsynaptic
5HT2 receptors, implying less sexual dysfunction but possible
worsening of the symptoms of OCD (obsessive compulsive disorder),
and 5HT3 receptors, implying less nausea) receptors. In
addition, mitrazapine can induce weight gain and sedation.
The weight of the evidence base indicates that mirtazapine
is equally efficacious with other classes of antidepressants,
while appearing to have a statistical - though not clinical
- advantage in terms of achieving remission. In addition,
mirtazapine has a statistical advantage over SSRIs in terms
of reducing depression symptoms, but the difference is not
clinically important.
However, there is strong evidence that patients taking mirtazapine
are less likely to leave treatment early due to side effects.
In sum, therefore, although mirtazapine is as effective
as other antidepressants, it may have a clinical advantage
in terms of reducing side effects likely to lead to patients
leaving treatment early (NICE (2004): Depression:
Management of Depression in Primary and Secondary Care
[National Clinical Practice Guideline Number 23 (15 DEC
2004)]); also MHRA (2005): Safety
of Selective Serotonin Reuptake Inhibitor Antidepressants
[Letter to Healthcare Professionals (18 Feb 2005)]). Indeed,
one recent head-on comparison (Versiani et al., CNS Drugs
(2005): Comparison
of the effects of mirtazapine and fluoxetine in severely
depressed patients) found mirtazapine to
be as effective and well tolerated as fluoxetine in the
treatment specifically of patients with severe depression,
with mirtazapine producing significantly better improvements
on sleeping assessment, but in contrast to fluoxetine, mirtazapine-treated
patients experienced a mean weight gain of 0.8 +/- 2.7 kg
compared with a mean decrease in weight of 0.4 +/- 2.1 kg
for fluoxetine-treated patients.
Venlafaxine (Effexor)
Venlafaxine was the first of the new generation dual-action
antidepressants. It inhibits the reuptake of both serotonin
and noradrenaline, comparable to this activity in TCAs.
Its activity "character" is dose-dependent: at
the standard dose of 75 mg it is an SSRI, with dual action
emerging at doses of 150 mg and above. At these higher doses
it also inhibits dopamine reuptake. It presents has a broad
range of side effects similar to the TCAs and
SSRIs, and in addition can increase blood pressure at higher
doses; it is for these several reasons associated with a
high incidence of discontinuation symptoms.
Venlafaxine at any dose is clinically equi-efficacious on
all efficacy outcomes to other antidepressants, as well
as on most acceptability and tolerability outcomes. However,
there is some evidence that patients taking venlafaxine
are more likely to leave treatment early due to side effects,
particularly when low dose (<150 mg) venlafaxine is compared
with fluoxetine, although for inpatients, those taking venlafaxine
are less likely to stop treatment early compared to TCAs
and SSRIs
Note in addition that one small study of inpatients found
that venlafaxine was superior to SSRIs on efficacy. On the
other hand, in outpatients, there was some evidence for
increased efficacy compared to other antidepressants, but
only on response (NICE (2004): Depression:
Management of Depression in Primary and Secondary Care
[National Clinical Practice Guideline Number 23 (15 DEC
2004)]); also MHRA (2005): Safety
of Selective Serotonin Reuptake Inhibitor Antidepressants
[Letter to Healthcare Professionals (18 Feb 2005)]). The
study by P. Vis (Ann Pharmacother (2005): Duloxetine
and Venlafaxine-XR in the Treatment of Major Depressive
Disorder: A Meta-Analysis of Randomized Clinical Trials)
was the first to compare the efficacy and safety of duloxetine
(Cymbalta) and extended-release venlafaxine (Effexor-XR)
finding a favorable - but not statistically significant
- trend in remission and response rates compared with duloxetine;
dropout rates and adverse events did not differ between
the two agents.
Also, as noted above, the meta-analyses of Hansen et al.
(Ann Intern Med (2005): Efficacy
and safety of second-generation antidepressants in the treatment
of major depressive disorder) did show a
modest but statistically significant additional treatment
effect for sertraline (Zoloft) and venlafaxine (Effexor)
compared with fluoxetine (Prozac, Sarafem). Note however
that the Berney's recent review (Dialogues Clin Neurosci
(2005): Dose-response
relationship of recent antidepressants in the short-term
treatment of depression) found that the strategy
of dose increase may be relevant for venlafaxine, in order
to increase the number of responders.
Duloxetine (Cymbalta):
Duloxetine is a serotonin-norepinephrine reuptake inhibitor
(SNRI) for treatment of MDD (and for urinary incontinence).
Studies support the efficacy and safety of 40-60 mg twice
daily for the treatment of acute MDD (Dugan, Ann Pharmacother
(2004): Duloxetine:
A Dual Reuptake Inhibitor); Kirwin &
Gören (Pharmacotherapy (2005): Duloxetine:
a dual serotonin-norepinephrine reuptake inhibitor for treatment
of major depressive disorder). Adverse effects
have been of mild to moderate severity and are considered
to be transient. Although cardiovascular effects (increased
heart rate or blood pressure) may present, these do not
appear to be clinically significant. Overall, duloxetine
appears to be a well tolerated, safe and effective antidepressant.
The review of Cowen et al. (Curr Med Res Opin (2005): Efficacy,
safety and tolerability of duloxetine 60 mg once daily in
major depression) found that multiple RCTs
have demonstrated the efficacy of duloxetine 60mg once daily
for the treatment of depression in both the short and long
term, finding in addition that duloxetine significantly
reduces the general aches and pains that frequently accompany
MDD, all with an acceptable tolerance. The most frequently
observed adverse events with duloxetine were nausea, dry
mouth and somnolence; with respect to nausea, however, it
was mild to moderate, and resolved rapidly with continued
treatment (Greist et al., Clin Ther (2004): Incidence
and duration of antidepressant-induced nausea: duloxetine
compared with paroxetine and fluoxetine).
Importantly, duloxetine did not appear to have a clinically
significant effect on blood pressure.
-
Dose Escalation:
Adli et al. (Eur Arch Psychiatry Clin Neurosci (2005): Is
dose escalation of antidepressants a rational strategy after
a medium-dose treatment has failed? A systematic review)
examined the issue of whether high-dose treatment, i.e.,
maximizing the dose of antidepressants, as is widely recommended
in cases of non-response to medium-dose treatment, is scientifically
supported, concluding that based on available data highdose
antidepressant treatment of patients refractory to medium-dose
treatment is recommended for tricyclic compounds but not
for SSRI, with some data suggesting beneficial efficacy
of ultra-high doses of the irreversible MAOI tranylcypromine.
However Berney's recent review (Dialogues Clin Neurosci
(2005): Dose-response
relationship of recent antidepressants in the short-term
treatment of depression) found that the strategy
of dose increase may be relevant for venlafaxine, in order
to increase the number of responders.
-
Acupuncture:
Smith and Hay (Cochrane Database Syst Rev (2005): Acupuncture
for depression) concluded that "there
is insufficient evidence to determine the efficacy of acupuncture
compared to medication, or to wait list control or sham
acupuncture, in the management of depression. Scientific
study design was poor and the number of people studied was
small."
-
St.
John's Wort:
The latest evidence from high-quality systematic reviews
demonstrates that St. John's Wort (SJW) is safe and effective
for short-term (six to eight weeks) relief of mild to moderate
depression in adults (see the distillation by Malaty of
the Cochrane Review, in Am Fam Physician (2005): St.
John's Wort for Depression; Linde et al.,
Cochrane Review (2005): St
John's Wort for depression); see also Roder
et al (Fortschr Neurol Psychiatr (2004: Meta-Analysis
of Effectiveness and Tolerability of Treatment of Mild to
Moderate Depression with St. John's Wort).
However Linde (Br J Psychiatry (2005): St
John's Wort for depression: meta-analysis of randomised
controlled trials) - reviewing much the same
literature of RCT's - finds that the evidence inconsistent
and confusing, noting that larger placebo-controlled trials
restricted to patients with major depression showed only
minor effects over placebo, while older and smaller trials
not restricted to patients with major depression showed
marked effects. But the same author's (Linde & Knuppel,
Phytomedicine (2005): Large-scale
observational studies of hypericum extracts in patients
with depressive disorders - a systematic review)
review of large-scale observational studies concludes that
SJW extracts are well tolerated and seem to be effective
in routine treatment of mild to moderate depressive disorders.
Against this, however, at least one later sufficiently powered
RCT comparing SJW with paroxetine (Paxil) in the treatment
of moderate to severe major depression - not mild to moderate,
as in previous studies - found that SJW (as a hypericum
extract WS 5570) was at least as effective as paroxetine
and was better tolerated (Szegedi et al., BMJ (2005): Acute
treatment of moderate to severe depression with hypericum
extract WS 5570 (St John's Wort): randomised controlled
double blind non-inferiority trial versus paroxetine).
In addition, the non-inferiority study of Gaspar et al.
(Pharmacopsychiatry (2005): Efficacy
and tolerability of hypericum extract STW3 in long-term
treatment with a once-daily dosage in comparison with sertraline)
found SJW both not inferior to sertraline (Zoloft) for the
treatment of moderate depression and well-tolerated, using
a once-daily dose of 612 mg of hypericum extract given for
up to 24 weeks. See also the noncomparative RCT prospective
study of Uebelhack et al. (Adv Ther (2004): Efficacy
and tolerability of Hypericum extract STW 3-VI in patients
with moderate depression: a double-blind, randomized, placebo-controlled
clinical trial) confirmed the clinical efficacy
and tolerability of oral Hypericum extract STW 3-VI (Laif)
900 mg once daily for the treatment of moderate depression.
Furthermore, a double-blind, randomized, placebo-controlled,
multicenter clinical study (Gastpar et al., Pharmacopsychiatry
(2006): Comparative Efficacy and Safety of a Once-Daily
Dosage of Hypericum Extract STW3-VI and Citalopram in Patients
with Moderate Depression: A Double-Blind, Randomised, Multicentre,
Placebo-Controlled Study) demonstrated the
non-inferiority and safety of a hypericum extract compared
with citalopram (Celexa) in the treatment of moderate depression.
Mannel (Drug Saf (2004): Drug
interactions with St John's Wort : mechanisms and clinical
implications) has reviewed preclinical and
clinical evidence relating to drug interactions with SJW
(Hypericum perforatum), finding sufficient evidence from
interaction studies and case reports to suggest that St
John's Wort may induce the cytochrome P450 (CYP) 3A4 enzyme
system and the P-glycoprotein drug transporter in a clinically
relevant manner, thereby reducing efficacy of co-medications,
further finding that drugs most prominently affected and
contraindicated for concomitant use with St John's Wort
are metabolized via both CYP3A4 and P-glycoprotein pathways,
and these include HIV protease inhibitors, HIV non-nucleoside
reverse transcriptase inhibitors (only CYP3A4), the immunosuppressants
cyclosporin and tacrolimus, and the antineoplastic agents
irinotecan and imatinib mesylate. Mannel speculates in addition
that efficacy of hormonal contraceptives may be impaired,
but this is based only on case reports of irregular bleedings
and unwanted pregnancies.
Despite this, Knuppel and Linde's safety review (J Clin
Psychiatry (2004): Adverse
effects of St. John's Wort: a systematic review)
concludes that hypericum extracts are well tolerated and
safe if taken under control of a physician who is aware
of potentially relevant risks in specific circumstances.
Finally, note that NICE (2004): Depression:
Management of Depression in Primary and Secondary Care
[National Clinical Practice Guideline Number 23 (15 DEC
2004)] and MHRA (2005): Safety
of Selective Serotonin Reuptake Inhibitor Antidepressants
[pdf] (Letter to Healthcare Professionals (18 Feb 2005))
concluded that St Johns Wort is more effective than
placebo on achieving response in both moderate and severe
depression, and on reducing depression symptoms in moderate
depression, and that furthermore there appears to be no
difference between St Johns Wort and other antidepressants,
other than in moderate depression where it is better at
achieving response, and in severe depression where it is
less effective than low-dose antidepressants in achieving
response. St Johns Wort appears more acceptable than
antidepressants, particularly TCAs, with fewer people leaving
treatment early due to side effects and reporting adverse
events. Despite this, NICE and MHRA do not recommend SJW,
largely consequent to the uncertainty about appropriate
doses, variation in the nature of preparations and potential
serious interactions with other drugs
(including oral contraceptives, anticoagulants and anticonvulsants).
-
SAMe:
Some studies of wide methodological quality have suggested
that S-adenosylmethionine (SAMe) supplementation may be
beneficial in the treatment of depression, leading Williams
et al. (Clin Invest Med (2005): S-adenosylmethionine
(SAMe) as treatment for depression: a systematic review)
to undertake a systematic review, concluding that although
the studies reviewed were short term, nonetheless there
appears to be a role for SAMe in the treatment of major
depression in adults.
-
Light
Therapy and Seasonal Affective Disorder (SAD):
Light therapy (as white bright light (10,000 lux, for one
hour daily) has been suggested in treating mood disorders,
especially those exhibiting seasonal variation (seasonal
affective disorder, or SAD. Golden et al. (Am J Psychiatry
(2005): The
Efficacy of Light Therapy in the Treatment of Mood Disorders:
A Review and Meta-Analysis of the Evidence)
have undertaken a comprehensive systematic review and meta-analysis
of randomized controlled trials, concluding that the balance
of RCT evidence suggests that bright light treatment and
dawn simulation for seasonal affective disorder is efficacious,
with effect sizes equivalent to those in most antidepressant
pharmacotherapy trials, furthermore finding that bright
light was efficacious and comparable in effect to most antidepressants
even for nonseasonal depression. This latter
result has been independently confirmed by Martiny et al.
(Acta Psychiatr Scand (2005): Adjunctive
bright light in non-seasonal major depression: results from
clinician-rated depression scales).
Unfortunately, despite rigorous demonstration of efficacy
in high methodologically sound trials and reviews, light
therapy remains severely underutilized in clinical practice
(see the sober commentary of M. Moran (Psychiatric News
(2005): Light
Therapy Kept in Dark Despite Effectiveness)
.
-
Treatment-resistant
Depression:
Patients presenting with treatment-resistant
depression are those whose depression symptoms have
failed to respond to two or more antidepressants at an adequate
dose for an adequate duration given sequentially; the term
acute-phase non-responders captures those who
have failed only one course of antidepressants.
Treatment strategies deployed include:
Switching strategies
Venlafaxine for treatment
resistant depression
Augmentation strategies:
o antidepressant + lithium
o antidepressant + anticonvulsants
(lamotrigine, carbamazepine
or valproate)
o antidepressant + another antidepressant
o antidepressant + pindolol
o antidepressant +triiodothyronine (T3)
o antidepressant + benzodiazepine
o antidepressant + antipsychotic
o antidepressant + buspirone
Lithium and Suicidal Behavior Prevention
The recent systematic review of Capriani et al. (Am J Psychiatry
(2005): Lithium
in the Prevention of Suicidal Behavior and All-Cause Mortality
in Patients With Mood Disorders: A Systematic Review of
Randomized Trials)
found that lithium is effective in the prevention of suicide,
deliberate self-harm, and death from all causes in patients
with mood disorders (including unipolar depression, bipolar
disorder, schizoaffective disorder, dysthymia, and rapid
cycling).
Treatment Strategies - Efficacy Not
Demonstrated:
Along with the conclusions of NICE
(2004): Depression:
Management of Depression in Primary and Secondary Care
[National Clinical Practice Guideline Number 23 (15 DEC
2004)] and MHRA (2005): Safety
of Selective Serotonin Reuptake Inhibitor Antidepressants
[Letter to Healthcare Professionals (18 Feb 2005)], the
weight of the evidence base does not provide compelling
evidence for the efficacy of either particular switching
strategies or for deploying venlafaxine, although there
is some evidence to suggest a clinical advantage for high
dose venlafaxine (mean 269 mg) over paroxetine in terms
of achieving remission, but insufficient evidence that this
effect is evident with respect to response, mean endpoint
scores or tolerability. Similarly, there is insufficient
evidence to recommend the use of benzodiazepine augmentation
of antidepressants. Yet Rush et al. (N Engl J Med (2006):
Bupropion-SR, Sertraline, or Venlafaxine-XR
after Failure of SSRIs for Depression)
tested whether switching to one antidepressant is more effective
than switching to another after unsuccessful treatment for
depression with a SSRI (citalopram), finding that approximately
one in four patients had a remission of symptoms after switching
to another antidepressant, although there was no significant
difference between switching from citalopram to either sertraline,
venlafaxine, or bupropion.
In addition, augmentation of an antidepressant with carbamazepine,
lamotrigine, buspirone, pindolol, valproate or thyroid (T3)
supplementation is not motivated in the routine management
of treatment-resistant depression.
Treatment Strategies - Possibly Efficacious:
- Augmentation of antidepressant + antidepressant:
This can be considered for patients whose depression is
treatment-resistant and who are prepared to tolerate the
aggregate side effects. There is evidence for benefits from
the addition of mianserin (Bolvidon, Norval, Tolvan) or
mirtazapine (Remeron) to SSRIs, although mianserin should
be used with caution, particularly in older adults, because
of the risk of agranulocytosis. The recent
review of Dodd et al. (J Affect Disord (2005): To
combine or not to combine? A literature review of antidepressant
combination therapy) concluded that many
antidepressants can be usefully combined especially if they
engage separate mechanisms of action, and that antidepressant
combinations clinically provide a useful resort in otherwise
treatment resistant individuals.
In this connection, Rubio et al. (J Affect Disord (2005):
Reboxetine adjunct for partial
or nonresponders to antidepressant treatment)
in a prospective 6 weeks open-label study found that the
strategy of combination with reboxetine
(Edronax, Vestra), a selective norepinephrine reuptake inhibitor
(SNRI) with use currently limited to Europe, may be an effective
and well-tolerated tool in treatment-resistant patients
who have failed to adequately respond to monotherapy with
SSRIs, venlafaxine or mirtazapine. See also Fleischaker
et al. (CNS Drug Review (2004): The
selective norepinephrine reuptake inhibitor antidepressant
reboxetine: pharmacological and clinical profile),
and Kadhe et al. (J Postgrad Med (2003): Reboxetine:
A Novel Antidepressant).
And although we know from field experience that clinicians
often add a second medication to an initial, either ineffective
or partially effective antidepressant, until the study of
Trivedi et al. (N Engl J Med (2006): Medication
Augmentation after the Failure of SSRIs for Depression)
no randomized controlled trial has rigorously evaluated
the efficacy of this augmentation approach. These researchers
tested 851 adults with nonpsychotic major depressive disorder
without remission despite a mean of approximately three
months of citalopram (Celexa) therapy (with mean final dose,
55 mg per day), with 565 randomized to receive sustained-release
bupropion (Wellbutrin) (at a dose of up to 400 mg per day)
as augmentation and another 286 to receive buspirone (Buspar)
(at a dose of up to 60 mg per day) as augmentation, finding
both augmentations to be useful in clinical settings, but
noting that augmentation with sustained-release bupropion
offered the advantage of a greater reduction in the number
and severity of symptoms and fewer side effects and adverse
events.
- Augmentation of antidepressant
+ venlafaxine:
Venlafaxine should be considered for patients whose
depression has failed to respond to two adequate trials
of other antidepressants, with consideration given to high-dose
therapy if required, provided patients can tolerate the
side effects.
- Augmentation of antidepressant +
lithium:
A trial of lithium augmentation should be considered for
patients whose depression has failed to respond to several
antidepressants and who are prepared to tolerate the burdens
associated with lithium use.
- Augmentation of antidepressant +
phenelzine (MAOI):
Phenelzine should be considered for patients whose
depression has failed to respond to alternative antidepressants
and who are prepared to tolerate the side effects and dietary
restrictions associated with its use, although its toxicity
in overdose must be considered when prescribing for patients
at high risk of suicide.
- Augmentation of antidepressant +
aripiprazole
Two clinical studies (by Simon & Nemeroff, J Clin Psychiatry
(2005): Aripiprazole
augmentation of antidepressants for the treatment of partially
responding and nonresponding patients with major depressive
disorder, and by Papakostas et al., J Clin
Psychiatry (2005): Aripiprazole
Augmentation of Selective Serotonin Reuptake Inhibitors
for Treatment-Resistant Major Depressive Disorder)
suggest that the atypical antipsychotic aripiprazole (Abilify)
may be an effective augmentation strategy for improving
therapeutic response in patients with treatment-resistant
major depressive disorder when administered in combination
with standard antidepressant therapy, although confirming
controlled studies are needed.
- Augmentation of antidepressant +
metyrapone
Jahn et al. (Arch Gen Psychiatry (2004): Metyrapone
as Additive Treatment in Major Depression)
found that the anti-adrenal agent metyrapone (Metopirone)
is an effective adjunct in the treatment of major depression,
accelerating the onset of antidepressant action, and providing
a better treatment outcome compared with standard treatment
while sustaining antidepressive effect.
- Augmentation of antidepressant +
sulphiride
Uchida et al. (J Clin Psychopharmacol (2005): Combined
Treatment With Sulpiride and Paroxetine for Accelerated
Response in Patients With Major Depressive Disorder)
found that the addition of the dopamine-mediated agent sulpiride
(100 mg/d)) was safe and effective strategy for accelerating
antidepressant response in patients being treated with paroxetine
(10-40 mg/daily), with median times to response among responders
alone for the combined treatment being 2 weeks as opposed
to 6 weeks without sulpiride supplementation.
-
Adult
MDD, Antidepressants and Suicide:
Independent of the issue of suicide risk and SSRIs in children
and adolescents, there has lately been raised comparable
potential concerns re whether some SSRIs may cause the emergence
or worsening of suicidal ideation in vulnerable patients
(Cipriani, Barbui, and Geddes, BMJ (2005):
Suicide, depression, and antidepressants).
Three studies published in the 19 Feb 2005 issue of the
British Medical Journal (BMJ) explore this issue critically.
Fergusson et al (BMJ (2005): Association
between suicide attempts and selective serotonin reuptake
inhibitors: systematic review of randomised controlled trials)
in their systematic review of published RCTs comparing SSRIs
with either placebo or other antidepressants in patients
suffering from MDD and other clinical conditions found an
almost twofold increase in the odds of fatal and non-fatal
suicidal attempts in users of SSRIs compared with users
of placebo or other therapeutic interventions, excluding
tricyclics (where no differences were observed when overall
suicide attempts were compared between users of SSRIs and
TCAs). Note however that no increase in risk was seen when
only fatal suicidal attempts were compared between SSRIs
and placebo.
Underscoring the importance of full weighting of the evidence
by (regrettably rare) inclusion of unpublished studies,
Gunnell et al (BMJ (2005): Selective
serotonin reuptake inhibitors (SSRIs) and suicide in adults:
meta-analysis of drug company data from placebo controlled,
randomised controlled trials submitted to the MHRA's safety
review) included
for review both published and unpublished RCTs submitted
by pharmaceutical companies to the safety review of MHRA
(Medicine and Healthcare products Regulatory Agency) of
the UK comparing SSRIs with placebo in adults with depression
and other clinical conditions, setting as outcome measures
(1) completed suicide, (2) non-fatal self harm, and (3)
suicidal thoughts. Their study found no evidence for an
increased risk of completed suicide, with only weak evidence
of an increased risk of self harm, and inconclusive evidence
of an increased risk of suicidal thoughts.
However, Martinez et al (BMJ (2005): Antidepressant
treatment and the risk of fatal and non-fatal self harm
in first episode depression: nested case-control study)
conducted a nested case-control study of information extracted
from GPRD (General Practice Research Database), analyzing
the risk of non-fatal self harm and suicide in patients
newly diagnosed with depression and prescribed SSRIs or
TCAs. They found in apparent contradiction to the other
studies cited that the SSRI users were not at increased
risk of suicide or non-fatal self harm in comparison with
TCA users, although in younger patients (aged 18 or less),
weak evidence indicated a higher risk of non-fatal self
harm for those prescribed SSRIs
There are some non-trivial methodological issues here, as
wisely observed by Cipriani, Barbui, and Geddes in their
editorial overview (BMJ (2005):
Suicide, depression, and antidepressants).
(1) RCTs typically included selected patient populations
with short periods of time for follow-up, and hence these
studies are not specifically designed to identify completed
or attempted suicides (with this outcome variable reported
only in a subgroup of studies). (2) Given that a diagnosis
of MDD was not required for review inclusion, these trials
necessarily represent different patient populations. (3)
Although data pooling procedures across hundreds of trials
increased the overall numbers, absolute numbers of patients
attempting and committing suicide remained very low, leaving
open the possibility that of a highly narrow margin of reporting
or not reporting a few cases that may have completely changed
overall outcome. (4) On the other hand, although the Martinez
et al study analyzed a large number of newly depressed patients,
the lack of randomization raises the problem of confounding
by indication: doctors might preferentially prescribe SSRIs
on safety grounds in patients at risk of suicide, and although
the authors adjusted statistically for this potential confounder,
the possibility that other known or unknown variables might
have acted in unpredictable ways cannot be ruled out.
Taking into account these methodological limitations, some
lessons for clinical practice can nonetheless be drawn.
Given the totality and weight of current evidence, there
appears to date no clear relation between SSRIs and suicide,
and together with available compelling evidence of efficacy
of treatment of moderate to severe MDD with antidepressants,
this should encourage the prescription dose-effective antidepressants
for this patient population. At the same time, prescribers
should be aware that SSRIs, like the earlier TCAs, may induce
or worsen suicidal ideation and suicide attempts especially
during the early treatment phases, likely consequent to
the fact that of their particular propensity to induce agitation
and activation at that time.
To address this, prescribers should schedule frequent follow
up, possibly also enlisting a supporting role for family
and caregivers, during these at-risk early phases of treatment,
and MDD patients should be advised against abrupt treatment
withdrawal, given the adverse risk of discontinuation reactions.
Note that these indications apply to adults MDD patients
only: in children and adolescents the balance between benefits
and harms appears to be negative (except possibly for fluoxetine
(Prozac), the only presently FDA=approved agent in these
applications), given minimal evidence of efficacy and accruing
evidence of an association between exposure to SSRIs, and
other antidepressant drugs, and the emergence of suicidal
ideation and behaviors. Such risk, coupled with the lack
of data on the long term impact of exposure of a developing
brain to antidepressant drugs, discourages routine prescription
of antidepressant drugs in children and adolescents.
|
SSRIs and Sexual
Dysfunction
-
The
problem of SSRI-induced SD:
[SD = sexual dysfunction]
It is now well-known that certain antidepressants can both
(1) cause de-novo sexual dysfunction in a person with no
such dysfunction prior to treatment, or (2) further worsen
preexisting adverse sexual symptoms, thus causative of SD
(sexual dysfunction). SD appears to be independent of the
not infrequent association of diminished sexual interest
in depressive states, both unipolar and bipolar.
These effects are commonly and most frequently observed
with SSRIs (selective serotonin reuptake inhibitors), and
it would appear that their incidence has been underestimated
until recently. SD may manifest for men or women differentially
across symptoms such as erectile dysfunction, diminished
libido and delayed/attenuated or absent orgasm (dysorgasmia
or anorgasmia).
-
Treating
SD - Drug Holidays:
The Rothschild study (J Clin Psychiatry:
Sexual
side effects of antidepressants) found
that for patients with sexual dysfunction secondary to SSRIs,
a two-day drug holiday (skipping Friday/ Saturday, recommencing
Sunday afternoon) improved sexual function with no loss
in antidepressant efficacy [for those on paroxetine (Paxil)
and sertraline (Zoloft), but not for those on fluoxetine
(Prozac), probably due to the latter's relatively longer
half-life].
-
Treating
SD - Buspirone:
The Norden study (Depression:
Buspirone
treatment of sexual dysfunction associated with selective
serotonin reuptake inhibitors) showed
improvement in SD with adjunctive dosing of the anxiolytic
buspirone (Buspar), earlier shown in case reports to reverse
sexual side effects, at 15 - 60 mg/daily, with more improvement
at the higher range during four weeks of treatment. (It
is interesting to note that a later RCT study of buspirone,
amantadine, and placebo, found significant and equivalent
improvement in all three arms of the study [see Michelson
et al, J Am Psychiatry: Female
sexual dysfunction associated with antidepressant administration,
although Evidencewatch
notes that the study may have encountered
some methodological constraints, including a subject population
limited to premenopausal women, so further studies are needed
to be wholly determinative]). Buspirone's efficacy in SD
treatment may be consequent to its dopaminergic activity,
or its serotonin-1A receptors partial agonist effect, or
possibly its direct suppression of SSRI-induced prolactin
elevation (buspirone's a2 antagonist major metabolite is
known to facilitate sexual behavior in animals).
-
Treating
SD - Gingko Biloba
:
Cohen et al [J Sex Marital Ther:
Gingko
biloba for antidepressant-induced sexual dysfunction]
found improvement of SSRI-induced
SD through administration of Gingko biloba within an effective
range of 60 - 240 mg/daily. However, it should be noted
that two later studies [Ashton et al, Am J Psychiatry:
Antidepressant-Induced
Sexual Dysfunction and Ginkgo Biloba, and
Kang et al, Hum Psychopharmacol: A
placebo-controlled, double-blind trial of Ginkgo biloba
for antidepressant-induced sexual dysfunction]
failed to confirm efficacy over placebo level, and given
methodological issues, further RCTs are needed to be determinative.
-
Treating
SD - Yohimbe:
Woodrum [Ann Pharmacother: Management
of SSRI-induced sexual dysfunction]
reports on the efficacy of the natural presynaptic a2-blocker
Yohimbe in treating SSRI-induced decreased libido and anorgasmia,
in an on demand scenario: using a dose from 5.4 to 16.2
mg, taken as needed 1 to 4 hours before intended sexual
intercourse. (See also the comprehensive review by Adimoelja
in Int J Androl: Phytochemicals
and the breakthrough of traditional herbs in the management
of sexual dysfunctions).
-
Treating
SD - Mirtazapine / Nefazodone:
The postsynaptic serotonin antagonist
mirtazapine (Remeron), a relatively new antidepressant,
is a potent 5-HT2 and 5-HT3 antagonist, with additional
a2-antagonistic properties; therefore, mirtazapines
antagonistic action can improve or resolve adverse SD (probably
mediated through 5-HT2 stimulation); see Farah in J Clin
Psychiatry: Relief
of SSRI-induced sexual dysfunction with mirtazapine treatment
and Zajecka in J Clin Psychiatry:
Strategies
for the treatment of antidepressant-related sexual dysfunction).
Both mirtazapine and nefazodone (Serzone) as postsynaptic
serotonin antagonists, appear to have minimal, if any, adverse
effect on sexual functioning, and hence these antidepressants
may be viable first-line agents for treating depression
in scenarios requiring avoidance of SD, and have furthermore
been shown to improve SSRI-induced sexual side effects when
used in an additive antidote role. On nefazodone-aided reduction
in SD, see Cleman et al, J Clin Psychiatry: Nefazadone
and the treatment of nonparaphilic compulsive sexual behavior:
A retrospective study).
As noted above, Michelson et al failed to confirm efficacy
of mirtazapine over placebo [J Am Psychiatry: Female
sexual dysfunction associated with antidepressant administration],
but Evidencewatch
notes that the study may have encountered
some methodological constraints, including a subject population
of limited to premenopausal women, so further studies are
needed to be wholly determinative.
-
Treating
SD - Sidenafil:
Sidenafil
(Viagra), approved for male erectile dysfunction, is a PDE5
inhibitor (competitive inhibitor of cGMP-specific phosphodiesterase
(PDE) type 5) and so increases nitric oxide production,
yielding smooth muscle relaxation and increased blood flow
to genital tissues. Several studies have found proven it
to reverse sexual side effects of SSRIs {see Zajecka in
J Clin Psychiatry: Strategies
for the treatment of antidepressant-related sexual dysfunction],
but recent studies have also proven efficacy in the treatment
of female sexual dysfunction [see especially Berman et al,
J Sex Marital Ther: Effect
of sildenafil on subjective and physiologic parameters of
the female sexual response in women with sexual arousal
disorder, also Caruso
et al, BJOG: Premenopausal
women affected by sexual arousal disorder treated with sildenafil:
a double-blind, cross-over, placebo-controlled study,
and most recently, Berman et al, J Urol: Safety
and efficacy of sildenafil citrate for the treatment of
female sexual arousal disorder: a double-blind, placebo
controlled study].
Its positive mechanism of action in this context appears
to be to increase blood flow to the clitoris and vagina;
usual effective dose range appears to be 50 - 100 mg, and
can be taken as needed within 30 - 60 minutes of intended
sexual activity.
-
Treating
SD - Bupropion:
The antidepressant bupropion (Wellbutrin)
demonstrates norephinephrine- and dopamine-enhancing activity.
The earlier study of Clayton et al, J Clin Psychiatry: Substitution
of an SSRI with bupropion sustained release following SSRI-induced
sexual dysfunction
had found that bupropion alleviates SSRI-induced sexual
dysfunction, with sexual functioning improving after the
addition of bupropion SR to SSRI regimen (and continuing
to improve, after SSRI discontinuation, with bupropion SR
therapy alone), although some patients withdrew during the
study consequent to bupropion side effects. Another most
recent controlled study [Clayton, J Clin Psychiatry:
A
Placebo-Controlled Trial of Bupropion SR as an Antidote
for Selective Serotonin Reuptake Inhibitor-Induced Sexual
Dysfunction, has re-confirmed
these findings, showing bupropion SR to be an effective
antidote to SSRI-induced SD, producing an increase in desire
to engage in sexual activity and frequency of engaging in
sexual activity, compared with placebo.
-
Treating
SD - Fluvoxamine:
Although SSRI-induced SD is now well
documented, it must be countenanced that some patients exhibiting
SD may be solely, or maximally, responsive to SSRI antidepressants.
In this scenario, an earlier study of Banov had found that
the SSRI fluvoxamine (Luvox) may exhibit less SD than other
SSRIs; however, a later multicenter study [Montejo et al,
J Clin Psychiatry: Incidence
of sexual dysfunction associated with antidepressant agents:
a prospective multicenter study of 1022 outpatients]
does not support this conclusion, and an Evidncewatch
review of the literature (as of Feb.,
2004) failed to discover other confirmation.
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