Prescription-event monitoring of 10,401 patients treated with fluvoxamine

Serum Concentration-Dose Relationship and Modulation Factors in Children and Adolescents Treated with Fluvoxamine

INTRODUCTION

Fluvoxamine is used in children and adolescents ('youths') for treating obsessive compulsive disorder (OCD) but also off-label for depressive and anxiety disorders. This study aimed to investigate the relationship between fluvoxamine dose and serum concentrations, independent correlates of fluvoxamine concentrations, and a preliminary therapeutic reference range (TRR) for youths with OCD and treatment response.

METHODS

Multicenter naturalistic data of a therapeutic drug monitoring service, as well as prospective data of the 'TDM Vigil study' (EudraCT 2013-004881-33), were analyzed. Patient and treatment characteristics were assessed by standardized measures, including Clinical Global Impressions-Severity (CGI-S) and -Change (CGI-I), with CGI-I of much or very much improved defining treatment response and adverse drug reactions using the Udvalg for Kliniske Undersogelser (UKU) Side Effect Rating Scale. Multivariable regression analysis was used to evaluate the influence of sex, age, body weight, body mass index (BMI), and fluvoxamine dose on fluvoxamine serum concentrations.

RESULTS

The study included 70 youths (age = 6.7-19.6 years, OCD = 78%, mean fluvoxamine dose = 140.4 (range = 25-300) mg/d). A weak positive correlation between daily dose and steady-state trough serum concentrations was found (rs = 0.34, p = 0.004), with dose variation explaining 16.2% of serum concentration variability. Multivariable correlates explaining 25.3% of the variance of fluvoxamine concentrations included higher fluvoxamine dose and lower BMI. Considering responders with OCD, the estimated TRR for youths was 55-371 ng/mL, exceeding the TRR for adults with depression of 60-230 ng/mL.

DISCUSSION

These preliminary data contribute to the definition of a TRR in youth with OCD treated with fluvoxamine and identify higher BMI as a moderator of lower fluvoxamine concentrations.

Which is the safest antidepressant to use in epilepsy?

Seizures are a serious adverse effect of many antidepressants: most, if not all, tricyclics (TCAs) lower the seizure threshold, some atypicals (e.g. maprotiline) are known to cause convulsions and seizures have been reported to occur with all selective serotonin reuptake inhibitors (SSRIs). Opinions vary on which is the safest antidepressant to use in epilepsy.

Incidence of early anxiety aggravation in trials of selective serotonin reuptake inhibitors in depression

OBJECTIVE

Selective serotonin reuptake inhibitors (SSRIs) may aggravate anxiety and agitation during the first days of treatment but the frequency of such reactions remains unknown.

METHOD

We analysed patient-level data from placebo-controlled trials of sertraline, paroxetine or citalopram in depressed adults. Somatic anxiety, psychic anxiety and psychomotor agitation as assessed using the Hamilton Depression Rating Scale (HDRS) were analysed in all trials (n = 8262); anxiety-related adverse events were analysed in trials investigating paroxetine and citalopram (n = 5712).

RESULTS

After one but not two weeks, patients on an SSRI were more likely than those on placebo to report enhanced somatic anxiety (adjusted risk 9.3% vs. 6.7%); likewise, mean rating of somatic anxiety was higher in the SSRI group. In contrast, patients receiving an SSRI were less likely to report aggravation of psychic anxiety (adjusted risk: 7.0% vs. 8.5%) with mean rating of psychic anxiety and agitation being lower in the SSRI group. The adverse event 'nervousness' was more common in patients given an SSRI (5.5% vs. 2.5%). Neither aggravation of HDRS-rated anxiety nor anxiety-related adverse events predicted poor antidepressant response.

CONCLUSION

Whereas an anxiety-reducing effect of SSRIs is notable already during the first week of treatment, these drugs may also elicit an early increase in anxiety in susceptible subjects that however does not predict a poor subsequent response to treatment.

Risk of seizures in transcranial magnetic stimulation: a clinical review to inform consent process focused on bupropion

OBJECTIVE

When considering repetitive transcranial magnetic stimulation (rTMS) for major depressive disorder, clinicians often face a lack of detailed information on potential interactions between rTMS and pharmacotherapy. This is particularly relevant to patients receiving bupropion, a commonly prescribed antidepressant with lower risk of sexual side effects or weight increase, which has been associated with increased risk of seizure in particular populations. Our aim was to systematically review the information on seizures occurred with rTMS to identify the potential risk factors with attention to concurrent medications, particularly bupropion.

DATA SOURCES

We conducted a systematic review through the databases PubMed, PsycINFO, and EMBASE between 1980 and June 2015. Additional articles were found using reference lists of relevant articles. Reporting of data follows Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

STUDY SELECTION

Two reviewers independently screened articles reporting the occurrence of seizures during rTMS. Articles reporting seizures in epilepsy during rTMS were excluded. A total of 25 rTMS-induced seizures were included in the final review.

DATA EXTRACTION

Data were systematically extracted, and the authors of the applicable studies were contacted when appropriate to provide more detail about the seizure incidents.

RESULTS

Twenty-five seizures were identified. Potential risk factors emerged such as sleep deprivation, polypharmacy, and neurological insult. High-frequency-rTMS was involved in a percentage of the seizures. None of these seizures reported had patients taking bupropion in the literature review. One rTMS-induced seizure was reported from the Food and Drug Administration in a sleep-deprived patient who was concurrently taking bupropion, sertraline, and amphetamine.

CONCLUSION

During the consent process, potential risk factors for an rTMS-induced seizure should be carefully screened for and discussed. Data do not support considering concurrent bupropion treatment as contraindication to undergo rTMS.

Is the exposure to antidepressant drugs in early pregnancy a risk factor for spontaneous abortion? A review of available evidences

Aim– To review studies conducted to establish the risk of spontaneous abortion (SA) in women exposed to anti-depressant drugs (ADs) during early pregnancy.Methods– By using different search terms, PubMed, Toxline, EMBASE, PsychINFO, and the Cochrane library databases were searched from January 1980 to March 2008, to identify studies assessing the risk of SA in women exposed to different classes of ADs during the first trimester of pregnancy.Results– Ten studies over 21 identified were selected for the analysis. All were performed prospectively and included as control group unexposed women, or exposed to non-teratogenic drugs or to placebo. In seven studies a depressive episode was specified as the reason for which the drug was prescribed, while the time of exposure was in nine.Conclusions– Only three studies over ten selected reported a significant association between an increased rate of SAs and early pregnancy exposure to some ADs. Many methodological flaws in the study design were found in all studies considered. Given this background and a lack of strong evidence on this issue, further prospective and better designed studies are needed to assess the risk of SA in pregnant women exposed to ADs against the risk of an untreated maternal depression.

Declaration of Interest:None.

Information about ADRs explored by pharmacovigilance approaches: a qualitative review of studies on antibiotics, SSRIs and NSAIDs

Background

Despite surveillance efforts, unexpected and serious adverse drug reactions (ADRs) repeatedly occur after marketing. The aim of this article is to analyse ADRs reported by available ADR signal detection approaches and to explore which information about new and unexpected ADRs these approaches have detected.

Methods

We selected three therapeutic cases for the review: antibiotics for systemic use, non-steroidal anti-inflammatory medicines (NSAID) and selective serotonin re-uptake inhibitors (SSRI). These groups are widely used and represent different therapeutic classes of medicines. The ADR studies were identified through literature search in Medline and Embase. The search was conducted in July 2007. For each therapeutic case, we analysed the time of publication, the strengths of the evidence of safety in the different approaches, reported ADRs and whether the studies have produced new information about ADRs compared to the information available at the time of marketing.

Results

79 studies were eligible for inclusion in the analysis: 23 antibiotics studies, 35 NSAID studies, 20 SSRI studies. Studies were mainly published from the end of the 1990s and onwards. Although the drugs were launched in different decades, both analytical and observational approaches to ADR studies were similar for all three therapeutic cases: antibiotics, NSAIDs and SSRIs. The studies primarily dealt with analyses of ADRs of the type A and B and to a lesser extent C and D, cf. Rawlins' classification system. The therapeutic cases provided similar results with regard to detecting information about new ADRs despite different time periods and organs attacked. Approaches ranging higher in the evidence hierarchy provided information about risks of already known or expected ADRs, while information about new and previously unknown ADRs was only detected by case reports, the lowest ranking approach in the evidence hierarchy.

Conclusion

Although the medicines were launched in different decades, approaches to the ADR studies were similar for all three therapeutic cases: antibiotics, NSAIDs and SSRIs. Both descriptive and analytical designs were applied. Despite the fact that analytical studies rank higher in the evidence hierarchy, only the lower ranking descriptive case reports/spontaneous reports provided information about new and previously undetected ADRs. This review underscores the importance of systems for spontaneous reporting of ADRs. Therefore, spontaneous reporting should be encouraged further and the information in ADR databases should continuously be subjected to systematic analysis.

Antidepressant-drug interactions are potentially but rarely clinically significant

The salient pharmacologic features of the selective serotonin reuptake inhibitors (SSRIs) discovered in the late 1980s included an in vitro ability to inhibit various cytochrome P450 enzymes (CYPs). Differences in potency among the SSRIs for CYP inhibition formed the basis of a marketing focus based largely on predictions of in vivo pharmacokinetic drug interactions from in vitro data, conclusions derived from case reports, and the extrapolation of the results of pharmacokinetic studies conducted in healthy volunteers to patients. Subsequently introduced antidepressants have undergone a similar post hoc scrutiny for potential drug-drug interactions. Concern for the untoward consequences of drug interactions led the FDA to publish guidance for the pharmaceutical industry in 1997 recommending that in vitro metabolic studies be conducted early in the drug development process to evaluate inhibitory properties toward the major CYPs. However, the prevalence of clinically significant enzyme inhibition interactions occurring during antidepressant treatment remains poorly defined despite millions of exposures. Although lack of evidence does not equate to evidence of absence, sparse epidemiological and post-marketing surveillance data do not substantiate a conclusion that widespread morbidity results from antidepressant-induced drug interactions. This commentary discusses points of uncertainty and controversy in the field of drug interactions, notes areas where inadequate data exist, and suggests explanations for a low prevalence of serious interactions. The conclusion is drawn that drug interactions from CYP inhibition caused by the newer antidepressants are potentially, but rarely, clinically significant.

Antidepressants and seizures: emphasis on newer agents and clinical implications

Seizures are a known, relatively rare, consequence of antidepressant treatment. Risk estimates vary depending on the study, source of data and patient population, predisposed vs. nonpredisposed. For newer antidepressants (e.g. selective serotonin reuptake inhibitors, bupropion, mirtazepine, etc.), the risk is generally considered to be low (0.0%-0.4%) and not very different from the incidence of first seizure in the general population (0.07%-0.09%). Risk with tricyclic antidepressants at effective therapeutic doses is relatively high (0.4% to 1-2%). Seizure following overdose is a significant and relatively frequent event for some antidepressants. Patients being considered for antidepressant treatment should be screened for predisposition to seizures. Predisposed patients should receive antidepressants cautiously. The seizure potential of antidepressants in patients without a predisposition is low, especially for newer antidepressants. Seizure risk, along with other drug-related considerations, e.g. weight gain, sexual dysfunction and sedation, should be considered when prescribing an antidepressant.

Treatment of suicide attempters prior to hospital admission

OBJECTIVE

Numerous authors have reported serious shortcomings in the treatment of suicidal patients. This study examined the treatment suicide attempters admitted to a psychiatric hospital in Switzerland had received prior to the suicide attempt.

METHOD

Thirty-one patients were admitted to this hospital within a year, representing 36 suicide attempts, which corresponds to 6.5% of the annual admission number. Three of these patients were admitted twice, and one patient was admitted three times. Information on previous treatment was collected in personal interviews and included medication, and its dosage, at 1 month and 2 weeks prior to the suicide attempt, and whether the patient had received psychotherapy. In addition, details of the psychosocial event and the means of the suicide attempt were recorded.

RESULTS

Twenty-one patients had been prescribed psychotropic drugs in 24 events, but only in 17 events concerning 15 patients, antidepressants were prescribed prior to hospitalisation. Antipsychotics and benzodiazepines were prescribed in 6 and 21 events, respectively (including 8 events with hypnotics). None of the patients was treated with lithium. In 19 events, 16 patients had received psychotherapy prior to admission. In 32 events, psychotropic drugs were used for the suicide attempt.

CONCLUSION

The findings confirm the undertreatment of patients attempting suicide reported by other authors. In spite of the majority of patients being under psychiatric care, no adequate pharmacotherapy had been prescribed particularly for depressed patients.

Mood disorders in patients with epilepsy: epidemiology and management

Patients with epilepsy are at high risk for depression because of an incompletely understood combination of factors that may be both psychosocial and neurological. Interictal depression in patients with epilepsy is an undertreated condition, in part because of concern regarding drug interactions and the risk of exacerbating seizures with antidepressant treatment. Bipolar disorder is not described as occurring with a higher than expected frequency in the population with epilepsy, but high rates of depression and suicide are well recognised, highlighting the need for more emphasis on antidepressive treatment in this group of at-risk patients. Neurological factors, including site and lateralisation of seizure focus, may be important for the development of depression, with left-sided seizure foci having a higher association with depressive symptoms. Forced normalisation may be a factor in the paradoxical onset of depression in patients with epilepsy whose seizures suddenly become well controlled by anti-seizure treatment. Lowering of folic acid levels by some antiepileptic drugs (AEDs) may also influence the expression of depression in patients with epilepsy. New AEDs continue to emerge as beneficial treatments themselves for mood disorders, with lamotrigine, gabapentin and, to a lesser extent, topiramate having clinical trials data to support their use in patients with bipolar disease. Similar positive data are available for vagal nerve stimulation. Mood effects of AEDs can be complicated, however, as many of these drugs (e.g. tiagabine) have also been reported to cause depression as an adverse effect. Electroconvulsive therapy in depressed patients with epilepsy requires special consideration. The selective serotonin reuptake inhibitors (SSRIs) and antidepressants that act at multiple receptors (e.g. nefazodone, venlafaxine) are the most appropriate treatments for depressed patients with epilepsy. Among these agents, citalopram has a low risk of interactions with AEDs. Bupropion, clomipramine and maprotiline are associated with a greater risk of seizures compared with other antidepressants and consequently should be used with caution in the treatment of depression in patients with epilepsy.

Effects of psychotropic drugs on seizure threshold

Psychotropic drugs, especially antidepressants and antipsychotics, may give rise to some concern in clinical practice because of their known ability to reduce seizure threshold and to provoke epileptic seizures. Although the phenomenon has been described with almost all the available compounds, neither its real magnitude nor the seizurogenic potential of individual drugs have been clearly established so far. In large investigations, seizure incidence rates have been reported to range from approximately 0.1 to approximately 1.5% in patients treated with therapeutic doses of most commonly used antidepressants and antipsychotics (incidence of the first unprovoked seizure in the general population is 0.07 to 0.09%). In patients who have taken an overdose, the seizure risk rises markedly, achieving values of approximately 4 to approximately 30%. This large variability, probably due to methodological differences among studies, makes data confusing and difficult to interpret. Agreement, however, converges on the following: seizures triggered by psychotropic drugs are a dose-dependent adverse effect; maprotiline and clomipramine among antidepressants and chlorpromazine and clozapine among antipsychotics that have a relatively high seizurogenic potential; phenelzine, tranylcypromine, fluoxetine, paroxetine, sertraline, venlafaxine and trazodone among antidepressants and fluphenazine, haloperidol, pimozide and risperidone among antipsychotics that exhibit a relatively low risk. Apart from drug-related factors, seizure precipitation during psychotropic drug medication is greatly influenced by the individual's inherited seizure threshold and, particularly, by the presence of seizurogenic conditions (such as history of epilepsy, brain damage, etc.). Pending identification of compounds with less or no effect on seizure threshold and formulation of definite therapeutic guidelines especially for patients at risk for seizures, the problem may be minimised through careful evaluation of the possible presence of seizurogenic conditions and simplification of the therapeutic scheme (low starting doses/slow dose escalation, maintenance of the minimal effective dose, avoidance of complex drug combinations, etc.). Although there is sufficient evidence that psychotropic drugs may lower seizure threshold, published literature data have also suggested that an appropriate psychotropic therapy may not only improve the mental state in patients with epilepsy, but also exert antiepileptic effects through a specific action. Further scientific research is warranted to clarify all aspects characterising the complex link between seizure threshold and psychotropic drugs.

Antidepressant use in clinical practice: efficacy v. effectiveness

BACKGROUND

Although the efficacy of antidepressants has been demonstrated in randomised, controlled clinical trials, it is how an antidepressant is used in clinical practice that determines its clinical effectiveness, or real-world efficacy.

AIMS

To explore the frequency with which antidepressants are used at adequate dose and duration to obtain remission of symptoms and prevent relapse in clinical practice and discuss potential implications for clinical outcomes.

METHOD

Studies of antidepressant prescribing were reviewed and comparisons made between antidepressant classes and individual compounds within those classes.

RESULTS

Naturalistic studies show that patients who begin therapy on tricyclic antidepressants often receive sub-therapeutic doses for inadequate duration; conversely, patients who begin therapy on selective serotonin reuptake inhibitors more often receive an adequate dose of therapy for a longer duration. CONCLUSIONS; How antidepressants are used in clinical practice can determine the clinical outcomes that are achieved. Antidepressants that are more forgiving of sub-optimal prescribing and use patterns by providers and patients, respectively, may help to improve real-world efficacy.

Safety and tolerability considerations: tricyclic antidepressants vs. selective serotonin reuptake inhibitors

OBJECTIVE

An important consideration in the choice of an antidepressant is its safety and tolerability.

METHOD

We present a review of literature, clinical trials and meta-analyses regarding the safety and tolerability of the tricyclic antidepressants (TCAs) and the selective serotonin reuptake inhibitors (SSRIs) in depressed patients.

RESULTS

The SSRIs have a very favourable side-effect profile compared to the TCAs and are associated with fewer treatment discontinuations. Unlike the TCAs, they do not cause anticholinergic, hypotensive or sedating reactions, and are not associated with impaired cognitive function. Their most common side-effects (nausea, vomiting, nervousness, insomnia, headache and sexual dysfunction) are usually mild and typically disappear as treatment continues. The SSRIs also exhibit lower toxicity and lower lethality when taken in an overdose situation. Although the safety profiles of the principal SSRIs appear to be comparable, there is some data showing important differences in the severity and frequency of specific adverse events.

CONCLUSION

The SSRIs have a more favourable safety profile than the TCAs in both acute and long-term treatment of major depression.

Fluvoxamine as an adjunctive agent in schizophrenia

Schizophrenia is a common mental disorder that has an early onset and rates high as a cause of medical disability. Antipsychotic agents are the mainstay of treatment but response is often inadequate. Negative symptoms (disturbances in volition, social interaction and affective functions) are particularly difficult to treat and form a major obstacle to rehabilitation. A promising approach to improve response of negative symptoms has been to add a selective serotonin reuptake inhibitor (SSRI) antidepressant to antipsychotic treatment. This review examines evidence pertaining to the efficacy, tolerability, and safety of the SSRI fluvoxamine, combined with antipsychotic agents, in the treatment of negative symptoms in schizophrenia. Important methodological issues, such as differentiating primary and secondary negative symptoms, are discussed. The balance of available evidence indicates that fluvoxamine can improve primary negative symptoms in chronic schizophrenia patients treated with typical antipsychotics and suggests that it may also do so in some patients treated with clozapine. This combination is generally safe and well tolerated although, as antipsychotic drug concentrations may be elevated, attention to dose and drug monitoring should be considered appropriately. Combination with clozapine may require particular caution because of potential toxicity if serum clozapine levels rise steeply. The fluvoxamine doses effective in augmentation are lower than those usually used to treat depression. Evidence regarding the use of fluvoxamine augmentation to treat phenomena, such as obsessions and aggression, which may be associated with schizophrenia, is also examined. An important goal of future studies will be to define which patient groups can benefit from combined treatment.

Depression in epilepsy: a common but often unrecognized comorbid malady

Depressive disorders (DDs) represent the most frequent psychiatric comorbidity in epilepsy (1-5). Despite their relatively high prevalence, DDs remain unrecognized and untreated in many patients with epilepsy. The purpose of this review is to examine the reasons behind the failure to recognize and treat DDs in epilepsy. We highlight the essential epidemiologic, etiopathogenic, and clinical aspects that need to be considered in the evaluation of every epileptic patient and dedicate the last section of this paper to the review of the most relevant treatment issues. If we are successful in our goals, the reader will be impressed by the significant impact of DDs on the quality of life of these patients, and by the need to investigate treatment modalities with the same scientific rigor used in the assessment of efficacy of antiepileptic drugs in the control of seizures.

Antidepressant drugs and seizure susceptibility: from in vitro data to clinical practice

The use of antidepressant drugs (ADs) in patients with epilepsy still raises uncertainties because of the widespread conviction that this class of drugs facilitates seizures. A detailed knowledge of this issue in its various aspects may help in optimal management of patients suffering concurrently from epilepsy and depression. This article reviews the available data in vitro in animals and humans concerning the known potential of various ADs to induce epileptic seizures. Emphasis has been placed on those variables that may generate confusion in interpreting the results of the various studies. Most ADs at therapeutic dosages exhibit in nonepileptic patients a seizure risk close to that reported for the first spontaneous seizure in the general population (i.e., <0.1%). In patients taking high AD doses, seizure incidence rises markedly and may reach values up to 40%. With a patient history of epilepsy and/or concomitant drugs that act on neuronal excitability, low or therapeutic AD doses may be sufficient to trigger seizures. Experimental data are in partial conflict with human data on the relative potential seizure risk of the various ADs. Therefore, a reliable scale for assigning a relative value to an individual AD or to single AD classes cannot be made. It appears fair to say that maprotiline and amoxapine exhibit the greatest seizure risk, whereas trazodone, fluoxetine, and fluvoxamine exhibit the least. Some ADs may also display antiepileptic effects, especially in low doses, in experimental models of epilepsy and in humans, but the mechanism of this action is largely unknown. The available data suggest that ADs may display both convulsant and anticonvulsant effects and that the most important factor in determining the direction of a given compound in terms of excitation/inhibition is drug dosage. It is probable that drugs that increase serotonergic transmission are less convulsant or, even, more anticonvulsant than others. Because of mutual pharmacokinetic interactions between antiepileptic drugs and ADs, with consequent marked changes in plasma concentrations, it remains to be established whether or not plasma AD levels that are effective against depression also facilitate seizures. Finally, exploring the mechanisms through which ADs modulate neuronal excitability might open new possibilities in antiepileptic drug development.

Systematic review and guide to selection of selective serotonin reuptake inhibitors

A meta-analysis of 20 short term comparative studies of 5 selective serotonin reuptake inhibitors (SSRIs; citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline) has shown no difference in efficacy between individual compounds but a slower onset of action of fluoxetine. There were suggestions that fluoxetine caused more agitation, weight loss and dermatological reactions than the other SSRIs. More patients discontinued fluvoxamine and fewer patients stopped sertraline because of adverse effects than their comparator SSRIs. The most common adverse reactions to the SSRIs were gastrointestinal (especially nausea) and neuropsychiatric (particularly headache and tremor). Data from the Committee on Safety of Medicines showed more reports of suspected reactions (including discontinuation reactions) to paroxetine, and of gastrointestinal reactions to fluvoxamine and paroxetine, than the other SSRIs during their first 2 years of marketing. Prescription-event monitoring revealed a higher incidence of adverse events related to fluvoxamine than its comparators. There were higher incidences of gastrointestinal symptoms, malaise, sedation and tremor during treatment with fluvoxamine and of sedation, tremor, sweating, sexual dysfunction and discontinuation reactions with paroxetine. Fluoxetine was not associated with a higher incidence of suicidal, aggressive and related events than the other SSRIs. Patients have survived large overdoses of each of the compounds, but concern has been expressed over 6 fatalities following overdoses of citalopram. Drug interactions mediated by cytochrome P450 enzymes are theoretically less likely to occur during treatment with citalopram and sertraline, but there is a sparsity of clinical data to support this. Methodological difficulties and price changes do not allow choice for recommendations on the choice of SSRI based on pharmacoeconomic data. Taking into account the strengths and weaknesses of the methods used to compare drugs, guidelines to the selection of individual SSRIs in clinical practice are proposed. Citalopram should be avoided in patients likely to take overdoses. Fluoxetine may not be the drug of first choice for patients in whom a rapid antidepressant effect is important or for those who are agitated, but it may have advantages over other SSRIs in patients who are poorly compliant with treatment and those who have previously had troublesome discontinuation symptoms. Fluvoxamine, and possibly paroxetine, should not be used as first choice in patients especially prone to SSRI-related adverse reactions, while paroxetine should be avoided if previous discontinuation of treatment was troublesome. When in doubt about the risks of drug interactions, citalopram or sertraline should be considered given the lower theoretical risk of interactions.

The serotonin syndrome

The serotonin syndrome is characterized by mental status changes and a variety of autonomic and neuromuscular manifestations. Its duration is usually brief, resolving within hours provided that the inciting agent has been discontinued. In most cases, two or more types of medications known to increase the activity of serotonin at the 5-HT1A receptor are required to produce it, and it frequently begins soon after the initiation of a new treatment regimen. Treatment is largely supportive although limited clinical experience warrants the cautious use of specified agents. Although its overall incidence is unknown, it is probably low, and an appropriate level of suspicion coupled with an adequate knowledge of the patient's drug history remains the mainstay of diagnosis and treatment.

Epidemiology and relative toxicity of antidepressant drugs in overdose

Antidepressant drugs are currently the mainstay of treatment for all but the mildest forms of depression. Their effectiveness in the management of depressive illness is undisputed and their effectiveness in preventing suicide, while not proven, may be assumed. Nevertheless, of all the drugs that are taken in lethal overdose, prescribed antidepressants are among the most common. Epidemiological studies from several countries have provided evidence of marked differences in overdose toxicity between drug classes and, in some cases, between individual drugs within a class, with some of the older tricyclic antidepressants (TCAs) being the most toxic. Over 80% of all deaths arising from overdose of antidepressant medication in the UK between 1987 and 1992 were caused by 2 drugs: amitriptyline and dothiepin. Taken alone, this figure conveys little information about the toxicity of either drug. However, when considered within an epidemiological context, the evidence suggests that both drugs are highly toxic in overdose, a conclusion that is supported by animal studies of the toxicity of TCAs and by clinical evidence of overdose toxicity. This paper reviews the epidemiological evidence concerning the acute toxicity of antidepressant drugs and considers the interplay of factors that contribute to the toxicity which occurs when they are taken in acute overdose. The inherent toxicity of the drug appears to be the crucial factor and, although less well researched, prescribing practices and perception of toxicity are probable contributory factors.

Depressive illness and the possibilities of somatic antidepressant treatment

Depression constitutes a considerable mental health problem. Depression is too often unrecognized or unproperly treated, which causes distress, social impairment, and increased risk of mortality for the individual, and large costs for society. However, several efficient treatment modalities and strategies exist. Different somatic antidepressant treatments for short- and long-term therapy and their respective quality-of-life and economic aspects will be presented and discussed.

A comparison of fluvoxamine and fluoxetine in the treatment of major depression

This randomized, double-blind, parallel-group design study of 100 outpatients with major depressive disorder is the first study in the United States to compare the efficacy and tolerability of fluvoxamine (100-150 mg/day) and fluoxetine (20-80 mg/day). After a variable, single-blind, washout period, patients were randomized to receive either fluvoxamine (51 patients) of fluoxetine (49 patients) for 7 weeks. Efficacy was assessed with the 21-item Hamilton Rating Scale for Depression (HAM-D), and Clinical Global Impressions scale for severity and improvement. Eighty-four percent of each treatment group completed the study with each group having a mean score at end point of less than 10. Both groups demonstrated a 60% improvement in HAM-D scores over the 7-week trial. There were no statistically significant differences observed between the two groups on any efficacy parameter. The medications were well tolerated, with only two patients in each group who were terminated because of side effects. There were differences in the side-effect profiles, with fluvoxamine being associated with less nausea than fluoxetine. In summary, fluvoxamine and fluoxetine were equally effective in reducing depressive symptoms, but the two drugs displayed slightly different side-effect profiles.

ACE-inhibitor-induced cough, an adverse drug reaction unrecognised for several years: studies in prescription-event monitoring

OBJECTIVE. This study examines cough recorded in Prescription-Event Monitoring (PEM) of four ACE-inhibitors. Particular attention was paid to the study of enalapril because the drug was monitored before the causal relationship between cough and ACE-inhibitors had been widely accepted. RESULTS. Several factors which had obscured the causal relationship in the individual cases were found to be also an obstacle in PEM. For example, cough was a common and non-serious event and was under-reported in the PEM study of enalapril and the rate was not strikingly different from that recorded for other drugs. Cough induced by ACE-inhibitors has several characteristics which reduce the chance of a recognisable "signal'. The original questionnaires returned from doctors in the PEM study of enalapril have been reexamined. The observation that the rate of cough diminished after enalapril had been stopped rather than increased after starting, provided the best evidence of causality, because this was not affected by many biases such as the publicity that had occurred prior to doctors participating in PEM completed later reports.

Comparative safety and tolerability of selective serotonin reuptake inhibitors

The selective serotonin reuptake inhibitors (SSRIs) have the best established tolerance and safety profile of the available antidepressants. Evidence for this conclusion comes from controlled clinical trials, post-marketing surveillance, prescription audits and case reports. Comparative studies are sparse within the class of SSRIs, and methodological differences between studies are problematic, yet certain differences emerge in tolerability when comparing placebo-adjusted incidence rates for the most common adverse events. Fluoxetine commonly produces nervousness, anxiety, insomnia and headache. Sexual dysfunction is more common with sertraline. Dry mouth can occur from paroxetine, and gastrointestinal effects (cramps, diarrhoea) from sertraline. The incidence of nausea appears to be no greater for any particular drug, especially after several weeks of treatment. Hyponatraemia and extrapyramidal side effects are rare events reported with all SSRIs. General guidelines are given for choosing an initial SSRI according to adverse effect profile; however, inter-subject variability exists in the expression of adverse effects, as well as intra-subject variability during treatment, suggesting the development of pharmacodynamic tolerance. Thus, rational selection of an SSRI on the basis of comparative tolerability is possible, but largely empirical without further scientific evidence from clinical trials specifically designed to differentiate drugs according to their adverse effect profile.

Comparing SSRIs: From chemistry to clinical choice

Selective serotonin reuptake inhibitors (SSRIs) are widely accepted as the best available treatment for most forms of depression. However, to date, there has been little attempt to differentiate between the members of this class of drugs. Since, unlike the tricyclic antidepressants, the SSRIs have very different chemical structures, it is not unexpected that they may have different pharmacological properties. These differences in pharmacology may, in turn, be expressed in varying pharmacokinetic, efficacy, safety and tolerability profiles which mean that the SSRIs may be a less homogeneous class of compounds than is generally assumed. This review analyses the differences between the SSRIs with the intention of helping the practising clinician to select the most appropriate drug for a particular patient.