A comparison of the post-marketing safety of four selective serotonin re-uptake inhibitors including the investigation of symptoms occurring on withdrawal

Rebound activation of 5-HT neurons following SSRI discontinuation

Cessation of therapy with a selective serotonin (5-HT) reuptake inhibitor (SSRI) is often associated with an early onset and disabling discontinuation syndrome, the mechanism of which is surprisingly little investigated. Here we determined the effect on 5-HT neurochemistry of discontinuation from the SSRI paroxetine. Paroxetine was administered repeatedly to mice (once daily, 12 days versus saline controls) and then either continued or discontinued for up to 5 days. Whereas brain tissue levels of 5-HT and/or its metabolite 5-HIAA tended to decrease during continuous paroxetine, levels increased above controls after discontinuation, notably in hippocampus. In microdialysis experiments continuous paroxetine elevated hippocampal extracellular 5-HT and this effect fell to saline control levels on discontinuation. However, depolarisation (high potassium)-evoked 5-HT release was reduced by continuous paroxetine but increased above controls post-discontinuation. Extracellular hippocampal 5-HIAA also decreased during continuous paroxetine and increased above controls post-discontinuation. Next, immunohistochemistry experiments found that paroxetine discontinuation increased c-Fos expression in midbrain 5-HT (TPH2 positive) neurons, adding further evidence for a hyperexcitable 5-HT system. The latter effect was recapitulated by 5-HT1A receptor antagonist administration although gene expression analysis could not confirm altered expression of 5-HT1A autoreceptors following paroxetine discontinuation. Finally, in behavioural experiments paroxetine discontinuation increased anxiety-like behaviour, which partially correlated in time with the measures of increased 5-HT function. In summary, this study reports evidence that, across a range of experiments, SSRI discontinuation triggers a rebound activation of 5-HT neurons. This effect is reminiscent of neural changes associated with various psychotropic drug withdrawal states, suggesting a common unifying mechanism.

Continuous home cage monitoring of activity and sleep in mice during repeated paroxetine treatment and discontinuation

RATIONALE

Non-invasive home cage monitoring is emerging as a valuable tool to assess the effects of experimental interventions on mouse behaviour. A field in which these techniques may prove useful is the study of repeated selective serotonin reuptake inhibitor (SSRI) treatment and discontinuation. SSRI discontinuation syndrome is an under-researched condition that includes the emergence of sleep disturbances following treatment cessation.

OBJECTIVES

We used passive infrared (PIR) monitoring to investigate changes in activity, sleep, and circadian rhythms during repeated treatment with the SSRI paroxetine and its discontinuation in mice.

METHODS

Male mice received paroxetine (10 mg/kg/day, s.c.) for 12 days, then were swapped to saline injections for a 13 day discontinuation period and compared to mice that received saline injections throughout. Mice were continuously tracked using the Continuous Open Mouse Phenotyping of Activity and Sleep Status (COMPASS) system.

RESULTS

Repeated paroxetine treatment reduced activity and increased behaviourally-defined sleep in the dark phase. These effects recovered to saline-control levels within 24 h of paroxetine cessation, yet there was also evidence of a lengthening of sleep bouts in the dark phase for up to a week following discontinuation.

CONCLUSIONS

This study provides the first example of how continuous non-invasive home cage monitoring can be used to detect objective behavioural changes in activity and sleep during and after drug treatment in mice. These data suggest that effects of paroxetine administration reversed soon after its discontinuation but identified an emergent change in sleep bout duration, which could be used as a biomarker in future preclinical studies to prevent or minimise SSRI discontinuation symptoms.

Estimating Risk of Antidepressant Withdrawal from a Review of Published Data

Adaptation of the brain to the presence of a drug predicts withdrawal on cessation. The outcome of adaptation is often referred to as 'physical dependence' in pharmacology, as distinct from addiction, although these terms have unfortunately become conflated in some diagnostic guides. Physical dependence to antidepressants may occur in some patients, consistent with the fact that some patients experience withdrawal effects from these medications. It is thought that longer duration of use, higher dose and specific antidepressants affect the risk of antidepressant withdrawal effects as they might cause greater adaptation of the brain. We searched PubMed for relevant systematic reviews and other relevant analyses to summarise existing data on determinants of antidepressant withdrawal incidence, severity and duration. Overall, data were limited. From survey data, increased duration of use was associated with an increased incidence and severity of withdrawal effects, consistent with some evidence from data provided by drug manufacturers. Duration of use may be related to duration of withdrawal effects but data are heterogenous and sparse. Serotonin and noradrenaline reuptake inhibitors and paroxetine are associated with higher risks than other antidepressants, though data for some antidepressants are lacking. Higher doses of antidepressant has some weak association with an increased risk of withdrawal, with some ceiling effects, perhaps reflecting receptor occupancy relationships. Past experience of withdrawal effects is known to predict future risk. Based on these data, we outline a preliminary rubric for determining the risk of withdrawal symptoms for a particular patient, which may have relevance for determining tapering rates. Given the limited scope of the current research, future research should aim to clarify prediction of antidepressant withdrawal risk, especially by examining the risk of withdrawal in long-term users of medication, as well as the severity and duration of effects, to improve the preliminary tool for predictive purposes. Further research into the precise adaptations in long-term antidepressant use may improve the ability to predict withdrawal effects for a particular patient.

Effect of selective serotonin reuptake inhibitor discontinuation on anxiety-like behaviours in mice

BACKGROUND

Abrupt cessation of therapy with a selective serotonin reuptake inhibitor (SSRI) is associated with a discontinuation syndrome, typified by numerous disabling symptoms, including anxiety. Surprisingly, little is known of the behavioural effect of SSRI discontinuation in animals.

AIM

Here, the effect of SSRI discontinuation on anxiety-like behaviour was systematically investigated in mice.

METHODS

Experiments were based on a three-arm experimental design comprising saline, continued SSRI and discontinued SSRI. Mice were assessed 2 days after SSRI discontinuation over a 5-day period using the elevated plus maze (EPM) and other anxiety tests.

RESULTS

An exploratory experiment found cessation of paroxetine (12 days) was associated with decreased open-arm exploration and reduced total distance travelled, in male but not female mice. Follow-up studies confirmed a discontinuation effect on the EPM in male mice after paroxetine (12 days) and also citalopram (12 days). Mice receiving continued paroxetine (but not citalopram) also showed decreased open-arm exploration but this was dissociable from the effects of discontinuation. The discontinuation response to paroxetine did not strengthen after 28 days of treatment but was absent after 7 days of treatment. A discontinuation response was not discernible in other anxiety and fear-learning tests applied 3-5 days after treatment cessation. Finally, discontinuation effects on the EPM were typically associated with decreased locomotion on the test. However, separate locomotor testing implicated anxiety-provoked behavioural inhibition rather than a general reduction in motor activity.

CONCLUSION

Overall, this study provides evidence for a short-lasting behavioural discontinuation response to cessation of SSRI treatment in mice.

A Focus on Abuse/Misuse and Withdrawal Issues with Selective Serotonin Reuptake Inhibitors (SSRIs): Analysis of Both the European EMA and the US FAERS Pharmacovigilance Databases

Despite increasing reports, antidepressant (AD) misuse and dependence remain underestimated issues, possibly due to limited epidemiological and pharmacovigilance evidence. Thus, here we aimed to determine available pharmacovigilance misuse/abuse/dependence/withdrawal signals relating to the Selective Serotonin Reuptake Inhibitors (SSRI) citalopram, escitalopram, paroxetine, fluoxetine, and sertraline. Both EudraVigilance (EV) and Food and Drug Administration-FDA Adverse Events Reporting System (FAERS) datasets were analysed to identify AD misuse/abuse/dependence/withdrawal issues. A descriptive analysis was performed; moreover, pharmacovigilance measures, including the reporting odds ratio (ROR), the proportional reporting ratio (PRR), the information component (IC), and the empirical Bayesian geometric mean (EBGM) were calculated. Both datasets showed increasing trends of yearly reporting and similar signals regarding abuse and dependence. From the EV, a total of 5335 individual ADR reports were analysed, of which 30% corresponded to paroxetine (n = 1592), 27% citalopram (n = 1419), 22% sertraline (n = 1149), 14% fluoxetine (n = 771), and 8% escitalopram (n = 404). From FAERS, a total of 144,395 individual ADR reports were analysed, of which 27% were related to paroxetine, 27% sertraline, 18% citalopram, 16% fluoxetine, and 13% escitalopram. Comparing SSRIs, the EV misuse/abuse-related ADRs were mostly recorded for citalopram, fluoxetine, and sertraline; conversely, dependence was mostly associated with paroxetine, and withdrawal to escitalopram. Similarly, in the FAERS dataset, dependence/withdrawal-related signals were more frequently reported for paroxetine. Although SSRIs are considered non-addictive pharmacological agents, a range of proper withdrawal symptoms can occur well after discontinuation, especially with paroxetine. Prescribers should be aware of the potential for dependence and withdrawal associated with SSRIs.

A systematic review into the incidence, severity and duration of antidepressant withdrawal effects: Are guidelines evidence-based?

INTRODUCTION

The U.K.'s current National Institute for Health and Care Excellence and the American Psychiatric Association's depression guidelines state that withdrawal reactions from antidepressants are 'self-limiting' (i.e. typically resolving between 1 and 2weeks). This systematic review assesses that claim.

METHODS

A systematic literature review was undertaken to ascertain the incidence, severity and duration of antidepressant withdrawal reactions. We identified 24 relevant studies, with diverse methodologies and sample sizes.

RESULTS

Withdrawal incidence rates from 14 studies ranged from 27% to 86% with a weighted average of 56%. Four large studies of severity produced a weighted average of 46% of those experiencing antidepressant withdrawal effects endorsing the most extreme severity rating on offer. Seven of the ten very diverse studies providing data on duration contradict the U.K. and U.S.A. withdrawal guidelines in that they found that a significant proportion of people who experience withdrawal do so for more than two weeks, and that it is not uncommon for people to experience withdrawal for several months. The findings of the only four studies calculating mean duration were, for quite heterogeneous populations, 5days, 10days, 43days and 79weeks.

CONCLUSIONS

We recommend that U.K. and U.S.A. guidelines on antidepressant withdrawal be urgently updated as they are clearly at variance with the evidence on the incidence, severity and duration of antidepressant withdrawal, and are probably leading to the widespread misdiagnosing of withdrawal, the consequent lengthening of antidepressant use, much unnecessary antidepressant prescribing and higher rates of antidepressant prescriptions overall. We also recommend that prescribers fully inform patients about the possibility of withdrawal effects.

Antidepressants, withdrawal, and addiction; where are we now?

Controversy continues with regard to antidepressants and withdrawal. Recent debates have focused on the prevalence and length of withdrawal, and some continue to state that withdrawal from these compounds constitutes 'addiction'. In this editorial we examine the evidence underlying these recent debates. We acknowledge gaps in knowledge, and make suggestions for how the field can progress.

Recognising and managing antidepressant discontinuation symptoms

Antidepressant discontinuation symptoms occur with all classes of antidepressant. A well-described discontinuation syndrome occurs with the selective serotonin reuptake inhibitors, common symptoms including dizziness, headache, nausea and lethargy. Rare antidepressant discontinuation syndromes include extrapyramidal syndromes and mania/hypomania. All these syndromes, even isolated discontinuation symptoms, share three common features that facilitate diagnosis; abrupt onset within days of stopping the antidepressant, a short duration when untreated and rapid resolution when the antidepressant is reinstated. Clinicians need to be familiar with strategies for the prevention and management of such symptoms. Preventive strategies include warning patients about the possibility of discontinuation symptoms, encouraging good antidepressant adherence and tapering antidepressants at the end of treatment. Most symptoms are mild and short-lived. Consequently symptoms that follow planned termination of an antidepressant can often be managed by providing an explanation and reassurance. More severe symptoms should be treated symptomatically or the antidepressant restarted, in which case symptoms usually resolve within 24 h. More cautious tapering can then follow.

Effect of Abrupt Discontinuation of Antidepressants in Critically Ill Hospitalized Adults

OBJECTIVES

To determine whether discontinuation of chronic antidepressant therapy is associated with a higher risk of antidepressant discontinuation syndrome (ADS) symptoms in patients admitted to the intensive care unit (ICU) when compared with those who were continued on therapy and to identify factors associated with increased risk of ADS in this population.

DESIGN

Single-center retrospective observational cohort study.

SETTING

ICUs in a tertiary care hospital.

PATIENTS

A total of 106 adult patients, admitted to the ICU between September 2013 and August 2014, who had a length of stay of 72 hours or longer and who were receiving chronic selective serotonin inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs) before admission.

MEASUREMENTS AND MAIN RESULTS

Patients were classified as continued or discontinued from therapy based on initiation of home SSRI/SNRI therapy within 48 hours of admission. The primary end point was incidence of ADS symptoms. Type of symptoms, receipt of symptom-related therapies, and length of stay were also assessed. Sequential logistic regression analysis was used to determine the impact of discontinuation while controlling for other risk factors. Therapy was discontinued in 38.7% of patients. The risk of developing ADS symptoms was higher in discontinued patients (unadjusted odds ratio [OR] 2.6, 95% confidence interval [CI] 1.12-6.07, p=0.024). After adjusting for covariates, the odds of ADS increased (adjusted OR 3.8, 95% CI 1.3-11.7, p=0.018). Female sex was associated with an increase in risk of ADS (OR 3.4, 95% CI 1.2-10.0, p=0.026). Affective symptoms were the most prevalent type reported (34.1% vs 10.8%, p=0.005). Use of symptom-related therapies and length of stay did not differ between groups.

CONCLUSION

Abrupt discontinuation of SSRI/SNRI therapy increases the risk of ADS symptoms in critically ill patients, particularly in females. These results underscore the importance of continuation of home antidepressant therapy even in the setting of critical illness.

Withdrawal Symptoms after Selective Serotonin Reuptake Inhibitor Discontinuation: A Systematic Review

Background: Selective serotonin reuptake inhibitors (SSRI) are widely used in medical practice. They have been associated with a broad range of symptoms, whose clinical meaning has not been fully appreciated. Methods: The PRISMA guidelines were followed to conduct a systematic review of the literature. Titles, abstracts, and topics were searched using the following terms: 'withdrawal symptoms' OR 'withdrawal syndrome' OR 'discontinuation syndrome' OR 'discontinuation symptoms', AND 'SSRI' OR 'serotonin' OR 'antidepressant' OR 'paroxetine' OR 'fluoxetine' OR 'sertraline' OR 'fluvoxamine' OR 'citalopram' OR 'escitalopram'. The electronic research literature databases included CINAHL, the Cochrane Library, PubMed and Web-of-Science from inception of each database to July 2014. Results: There were 15 randomized controlled studies, 4 open trials, 4 retrospective investigations, and 38 case reports. The prevalence of the syndrome was variable, and its estimation was hindered by a lack of case identification in many studies. Symptoms typically occur within a few days from drug discontinuation and last a few weeks, also with gradual tapering. However, many variations are possible, including late onset and/or longer persistence of disturbances. Symptoms may be easily misidentified as signs of impending relapse. Conclusions: Clinicians need to add SSRI to the list of drugs potentially inducing withdrawal symptoms upon discontinuation, together with benzodiazepines, barbiturates, and other psychotropic drugs. The term 'discontinuation syndrome' that is currently used minimizes the potential vulnerabilities induced by SSRI and should be replaced by 'withdrawal syndrome'. © 2015 S. Karger AG, Basel.

How to switch to agomelatine after an unsuccessful try with paroxetine or venlafaxine

OBJECTIVE/INTRODUCTION

The present trial informs clinicians about switching conditions with the antidepressant agomelatine after the failure of a treatment with either paroxetine or venlafaxine.

METHODS

The total number of discontinuation-emergent symptoms, according to the Discontinuation-Emergent Signs and Symptoms checklist, was compared in double-blind conditions after 3 switching options: immediate substitution or initiation of agomelatine (25 mg/day p.o.) with either a short- or long-tapering of the previous drug. Secondary objectives included tolerability and safety assessments and the early clinical benefit after the switch.

RESULTS

For all switching options, a withdrawal syndrome was observed 1 week after cessation of the selective serotonin reuptake inhibitor (SSRI)/serotonin-norepinephrine reuptake inhibitor (SNRI) treatment. Psychic symptoms were the most frequently reported, and somatic symptoms were comparatively few. Early discontinuation symptoms after cessation of SSRI/SNRI treatment did not prejudice the antidepressant benefits of agomelatine over 8 weeks.

CONCLUSIONS

Both abrupt and start-taper switching with agomelatine are options in everyday practice for those patients who have not responded to either paroxetine or venlafaxine. However, regardless of the switching strategy, the present double-blind study shows that early discontinuation symptoms that arise upon cessation of SSRI/SNRI can alter the patients' perception of the clinical benefit of the new antidepressant. Both practitioners and patients must be warned about these early discontinuation symptoms to prevent the symptoms from being confounded with a lack of therapeutic benefit of the new treatment.

New insights on the antidepressant discontinuation syndrome

OBJECTIVE

Antidepressants are at best 50–55% effective. Non-compliance and the antidepressant discontinuation syndrome (ADS) are causally related yet poorly appreciated. While ADS is associated with most antidepressants, agomelatine seems to be devoid of such risk. We review the neurobiology and clinical consequences of antidepressant non-compliance and the ADS. Agomelatine is presented as a counterpoint to learn more on how ADS risk is determined by pharmacokinetics and pharmacology.

DESIGN

The relevant literature is reviewed through a MEDLINE search via PubMed, focusing on agomelatine and clinical and preclinical research on ADS.

RESULTS

Altered serotonergic dysfunction appears central to ADS so that how an antidepressant targets serotonin will determine its relative risk for inducing ADS and thereby affect later treatment outcome. Low ADS risk with agomelatine versus other antidepressants can be ascribed to its unique pharmacokinetic characteristics as well as its distinctive actions on serotonin, including melatonergic, monoaminergic and glutamatergic-nitrergic systems.

CONCLUSIONS

This review raises awareness of the long-term negative aspects of non-compliance and inappropriate antidepressant discontinuation, and suggests possible approaches to “design-out” a risk for ADS. It reveals intuitive and rational ideas for antidepressant drug design, and provides new thoughts on antidepressant pharmacology, ADS risk and how these affect long-term outcome.

Social inequalities in suicide: the role of selective serotonin reuptake inhibitors

We aimed to examine the relationship between socioeconomic status (SES) and suicide associated with the introduction and diffusion of selective serotonin reuptake inhibitors (SSRIs). Negative binomial regression was used to estimate county-level suicide rates among persons aged 25 years or older using death certificate data collated by the National Center for Health Statistics from 1968 to 2009; SES was measured using the decennial US Census. The National Health and Nutrition Examination Survey and the Medical Expenditure Panel Survey were used to measure SSRI use. Once SSRIs became available in 1988, a 1% increase in SSRI usage was associated with a 0.5% lower suicide rate. Prior to the introduction of SSRIs, SES was not related to suicide. However, with each 1% increase in SSRI use, a 1-standard deviation (SD) higher SES was associated with a 0.6% lower suicide rate. In 2009, persons living in counties with SES 1 SD above the national average were 13.6% less likely to commit suicide than those living in counties with SES 1 SD below the national average--a difference of 1.9/100,000 adults aged ≥25 years. Higher SSRI use was associated with lower suicide rates among US residents aged ≥25 years; however, SES inequalities modified the association between SSRI use and suicide.

Survey of symptoms associated with antidepressant discontinuation

Objectives: Literature reports on SSRI associated discontinuation symptoms are variable. As a result, the prevalence of an antidepressant halo effect can not be ruled out. This survey aims to assess the awareness and experience of these symptoms among doctors in Ireland.

Method: Questionnaires were sent to a random sample of 100 GPs, NCHDs and consultants. A questionnaire measured awareness, experience and reported severity, of SSRI discontinuation symptoms as opposed to TCAs, the latter being used as ‘controls’. Data was statistically analysed using SPSS (Windows Version 8.0).

Results: Response to the questionnaire was as follows: 37% of GPs (n = 37), 35% consultants (n = 35) and 18% NCHDs (n = 18). Comparisons were made between the three groups. There was significant variability in the reported recognition and severity of symptoms specific to the SSRI discontinuation syndrome within and between the groups. Overall NCHDs attribute less discontinuation symptoms to SSRIs (p = 0.038) and GPs attribute more to TCAs (p = 0.03).

Conclusions: Doctors tend to generalise discontinuation symptoms to all antidepressants with significant variation in reporting practices. Thus there is a need for randomised control studies to aid the recognition and prevention of the discontinuation syndrome.

The best next drug in the course of generalized anxiety disorders: the "PN-GAD-algorithm"

OBJECTIVE

Today, there are many pharmacotherapeutic options for generalized anxiety disorder (GAD). The question is, which is the best medication for a particular patient at a particular moment? This is especially challenging because GAD is by definition a chronic disorder and new interventions should learn from earlier experiences. An algorithm which can help to use pretreatment information for drug selection is the "Pretreatment - Next Treatment (PN) - Algorithm". This article introduces an PN-algorithm for GAD.

METHODS AND RESULTS

For the development of a GAD-specific PN-algorithm, all possible pharmacological options for GAD are reviewed and brought into a rank order on the basis of scientific evidence regarding efficacy, tolerability, or price: (1) pregabalin, (2) venlafaxine XR, (3) selective serotonin reuptake inhibitors, (4) tricyclic antidepressants, (5) buspirone, (6) antipsychotics, (7) benzodiazepines, and (8) hydroxyzine. Based on this hierarchy and patient-specific information, a decision algorithm is derived, which allows to assess and evaluate pretreatment and to select the drug with no contraindications, limited negative or convincing positive effects, or the option which has not been used so far but which is the next compound in the hierarchy.

CONCLUSIONS

The "PN-GAD-algorithm" can be easily translated into a checklist to support clinical decision-making. It can also help to increase patient empowerment and cooperation in long-term treatment.

Selective serotonin reuptake inhibitor antidepressant treatment discontinuation syndrome: a review of the clinical evidence and the possible mechanisms involved

Besides demonstrated efficacy, selective serotonin reuptake inhibitors (SSRIs) hold other advantages over earlier antidepressants such as greater tolerability and a wider range of clinical applications. However, there is a growing body of clinical evidence which suggests that SSRIs could, in some cases, be associated with a withdrawal reaction upon cessation of regular use. In addition to sensory and gastrointestinal-related symptoms, the somatic symptoms of the SSRI discontinuation syndrome include dizziness, lethargy, and sleep disturbances. Psychological symptoms have also been documented, usually developing within 1–7 days following SSRI discontinuation. The characteristics of the discontinuation syndrome have been linked to the half-life of a given SSRI, with a greater number of reports emerging from paroxetine compared to other SSRIs. However, many aspects of the neurobiology of the SSRI discontinuation syndrome (or SSRI withdrawal syndrome) remain unresolved. Following a comprehensive overview of the clinical evidence, we will discuss the underlying pathophysiology of the SSRI discontinuation syndrome and comment on the use of animal models to better understand this condition.

What is the difference between dependence and withdrawal reactions? A comparison of benzodiazepines and selective serotonin re-uptake inhibitors

AIMS

To explore the rationale for claiming that benzodiazepines cause dependence while selective serotonin re-uptake inhibitors (SSRIs) do not.

METHODS

We analysed the definitions of dependence and withdrawal reactions as they had appeared over time in the Diagnostic Statistical Manual of Mental Diseases (DSM) and the International Classification of Diseases (ICD). We also compared the discontinuation symptoms described for the two drug groups in a systematic review.

RESULTS

The definition of substance dependence has changed over time in both the DSM and ICD. In the most recent classifications several criteria, including behavioural, physiological and cognitive manifestations, must be fulfilled. This change was published with the revision of the DSM-III revision in 1987 (DSM-IIIR), after the recognition of benzodiazepine dependence and just before the SSRIs were marketed in 1987-88. We found that discontinuation symptoms were described with similar terms for benzodiazepines and SSRIs and were very similar for 37 of 42 identified symptoms described as withdrawal reactions.

CONCLUSIONS

Withdrawal reactions to selective serotonin re-uptake inhibitors appear to be similar to those for benzodiazepines; referring to these reactions as part of a dependence syndrome in the case of benzodiazepines, but not selective serotonin re-uptake inhibitors, does not seem rational.

A case report of onset of tinnitus following discontinuation of antidepressant and a review of the literature

This case report describes a 46-year-old woman with long-standing episodic severe depression (ICD-10 code F33) who discontinued venlafaxine over a 4-week taper after taking the antidepressant for 8 years. Severe discontinuation syndrome was experienced. Panic and relapse of depression occurred 2 months after achieving discontinuation, and the development of tinnitus took place concurrently to the discontinuation. The experience of the tinnitus as a side effect of discontinuation is different from cases reported in the literature in which the tinnitus was experienced when the antidepressant was started and ceased when the antidepressant was stopped. Here, the patient experienced the tinnitus as a discontinuation symptom, and it persisted even after the antidepressant was reintroduced. A review of the literature on antidepressant discontinuation syndrome is also provided.

Paroxetine for the treatment of depression: a critical update

INTRODUCTION

A growth in the market for antidepressants, paired with an ever-increasing population affected from depressive disorder, requires a critical re-evaluation of most prescribed antidepressants, in order to provide up-to-date practical prescribing information for clinicians. Paroxetine represents a widely prescribed and reliable antidepressant for the expert clinician, but the latest data do not rank it amongst the most effective and tolerable newer antidepressants.

AREAS COVERED

This paper reviews latest data on paroxetine and investigates its clinical efficacy and safety in different groups of patients.

EXPERT OPINION

In previous subanalysis and metaregression analysis, paroxetine failed to show clear differences in terms of efficacy across clinical subgroups. Thus, nowadays the pharmacokinetic and pharmacodynamic properties of the molecule are fundamental to guiding its prescription, both for efficacy and tolerability issues, for example, it can have a high impact on sexual function and weight should also be considered at the beginning of treatment. Since prescription is still based mainly on its side-effect profile, newer and more accurate directions for an individualized prescription are needed.

[Perioperative adverse events related to antidepressive agents use]

OBJECTIVE

Depression is the most common psychiatric disease, which is treated by the use of antidepressive agents possessing various mechanisms of action. Thus, the use in preoperative period of antidepressive agents is frequent (7% of patients scheduled for surgery). The objective of this review was to update the knowledge on the drug interactions between antidepressive agents and drugs used in perioperative period.

METHODS

(i) Medline and Ovid databases using combination of antidepressive agent and perioperative period as keywords; (ii) national and European epidemiologic database; (iii) expert recommendation and official French health agency; (iv) reference book chapters.

RESULTS

The clinical practice showed a limited risk of adverse event related to antidepressant agents interaction with perioperative used drugs. In the two past decades, few relevant observations of adverse event related with imipramine and monoamine oxidase inhibitors use was reported. The most recent antidepressive agents had no serious adverse interaction. Nevertheless, the serotonin syndrome has to be known as far as it is more and more reported. In case of hypotension, the use of vasopressive agent has to be careful because of excessive response.

The mechanisms of tolerance in antidepressant action

There is increasing awareness that, in some cases, long-term use of antidepressant drugs (AD) may enhance the biochemical vulnerability to depression and worsen its long-term outcome and symptomatic expression, decreasing both the likelihood of subsequent response to pharmacological treatment and the duration of symptom-free periods. A review of literature suggesting potential side effects during long treatment with antidepressant drugs was performed. Studies were identified electronically using the following databases: Medline, Cinahl, PsychInfo, Web of Science and the Cochrane Library. Each database was searched from its inception date to April 2010 using "tolerance", "withdrawal", "sensitization", "antidepressants" and "switching" as key words. Further, a manual search of the psychiatric literature has been performed looking for articles pointing to paradoxical effects of antidepressant medications. Clinical evidence has been found indicating that even though antidepressant drugs are effective in treating depressive episodes, they are less efficacious in recurrent depression and in preventing relapse. In some cases, antidepressants have been described inducing adverse events such as withdrawal symptoms at discontinuation, onset of tolerance and resistance phenomena and switch and cycle acceleration in bipolar patients. Unfavorable long-term outcomes and paradoxical effects (depression inducing and symptomatic worsening) have also been reported. All these phenomena may be explained on the basis of the oppositional model of tolerance. Continued drug treatment may recruit processes that oppose the initial acute effect of a drug. When drug treatment ends, these processes may operate unopposed, at least for some time and increase vulnerability to relapse. Antidepressant drugs are crucial in the treatment of major depressive episodes. However, appraisal and testing of the oppositional model of tolerance may yield important insights as to long-term treatment and achievement of enduring effects.

Barriers to achieving treatment goals: a focus on sleep disturbance and sexual dysfunction

BACKGROUND

Patients who meet the criteria for a major depressive episode experience a constellation of symptoms, and different symptom configurations may reflect distinct underlying neurological disturbances. Similarly, the differing receptor profiles of the various antidepressants may explain relatively low remission rates and persistent symptoms even after remission. In particular, depressed patients frequently display altered circadian rhythms, sleep disturbances, and diurnal mood variation. Exploring treatments that can restore mood while having a positive impact on circadian rhythms and sleep would greatly improve the ability to treat this core features of depression.

METHODS

The mechanisms of action of the various classes of antidepressants, their effects on sleep and issues beyond sleep, including sexual dysfunction, are explored, along with questions relating to adherence.

RESULTS

Unfortunately, persistent sleep problems are among the most difficult-to-treat residual symptoms of depression. Many of the currently available antidepressants have adverse effects on circadian processes, including sleep, and may actually worsen sleep problems. Tolerability is also an enduring issue; SSRI and SNRI antidepressants are associated with central nervous sysytem and gastrointestinal effects, sexual side effects and suicidality. Improved drug tolerability would not only minimize distressing adverse effects, but would also improve adherence, thus maximizing the chances of successful treatment.

CONCLUSIONS

The complexity of managing a major depressive episode is well illustrated by sleep disturbance and sexual dysfunction, two core symptoms of MDD that may also be caused or exacerbated by antidepressant therapy. Future antidepressants should alleviate symptoms without adversely affecting sleep or sexual function.

Hallucination induced by paroxetine discontinuation in patients with major depressive disorders

Discontinuation symptoms can follow the stoppage of almost all classes of antidepressants, including selective serotonin reuptake inhibitors. We report two cases suffering from visual and auditory hallucinations: Case 1 abruptly stopped taking paroxetine (20 mg/day), and Case 2 discontinued paroxetine after reducing the dose from 20 mg/day to 10 mg/day for 5 months. Both cases experienced visual and auditory hallucinations in addition to dizziness, headache, insomnia, and nausea a couple of days after paroxetine discontinuation. These observations suggest that hallucinations are a part of the discontinuation syndrome that results from paroxetine discontinuation. Physicians should be aware of this symptom.

Depression in adults: drug and physical treatments

INTRODUCTION

Depression may affect up to 10% of the population, with half of affected people having recurrence of their symptoms. In mild to moderate depression, there is no reliable evidence that any one treatment is superior in improving symptoms of depression, but the strength of evidence supporting different treatments varies. In severe depression, only prescription antidepressants and electroconvulsive therapy are known to improve symptoms.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments in mild to moderate and severe depression, and in treatment-resistant depression? Which interventions reduce relapse rates? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 88 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: antidepressant drugs (tricyclic antidepressants [including low-dose tricyclic antidepressants], selective serotonin reuptake inhibitors, monoamine oxidase inhibitors, or venlafaxine), continuing prescription antidepressant drugs, electroconvulsive therapy, exercise, lithium augmentation, pindolol augmentation, and St John's wort.

Antidepressant discontinuation manic states: a critical review of the literature and suggested diagnostic criteria

We critically appraised all published reports of hypomania and mania following antidepressant termination. To increase reliability and validity we devised diagnostic criteria for an antidepressant discontinuation or withdrawal 'manic state' based primarily on the Diagnostic and Statistical Manual of Mental Disorders, 4th edition substance withdrawal criteria. A systematic literature review identified 24 reports meeting our criteria. Mean age was 39 years (range 18-74), men and women were approximately equally represented, and more cases involved people with unipolar (n = 19) than bipolar disorder (n = 4). The median duration of preceding antidepressant treatment was 12 weeks (range 4 weeks-12 years). All major antidepressant classes were involved (tricyclic antidepressants = 13; selective serotonin reuptake inhibitors = 5; monoamine oxidase inhibitors = 3; selective serotonin-norepinephrine reuptake inhibitors = 2; miscellaneous = 1). More cases followed abrupt antidepressant withdrawal (n = 11) than a tapered withdrawal (n = 6). Six cases appeared to meet the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition for a manic episode, with two cases requiring inpatient admission. Of the 24 cases, nine resolved spontaneously without treatment (median duration = 25.5 days), six responded to antimanic drugs, four resolved following antidepressant reinstatement, and treatment was unclear in five cases. We conclude that antidepressant discontinuation hypomania/mania is a valid syndrome. It should be added to the differential diagnosis of hypomania/mania. The clinical implications and possible mechanisms are discussed.

Sensory disturbances associated with serotonin reuptake inhibitors: brief review

Serotonin reuptake inhibitors (SRIs) are occasionally associated with sensory symptoms, which are one of the less recognized adverse effects. A PUBMED search supplemented with manual search was made to review the relevant literature. Anesthesia, paresthesia, and mastalgia have been reported to occur with this group of medications. The possible pathophysiology and management strategies are discussed.

Discontinuation symptoms and taper/poststudy-emergent adverse events with desvenlafaxine treatment for major depressive disorder

The objective of this study was to assess discontinuation symptoms with desvenlafaxine (administered as desvenlafaxine succinate) treatment for major depressive disorder. Data were analyzed from nine 8-week, double-blind (DB), placebo-controlled studies of desvenlafaxine (50, 100, 200, or 400 mg/day; placebo, n = 319; desvenlafaxine, n = 578) and a relapse-prevention study [12-week, open-label (OL) 200 or 400 mg/day desvenlafaxine (n = 373); 6-month DB placebo (n = 73) or desvenlafaxine (n = 118)]. Rates of taper/poststudy-emergent adverse events were summarized. Discontinuation-Emergent Signs and Symptoms (DESS) checklist scores were analyzed in treatment completers at the end of OL and DB treatment. The most common (> or = 5%) taper/poststudy-emergent adverse events among desvenlafaxine patients were dizziness, nausea, headache, irritability, diarrhea, anxiety, abnormal dreams, fatigue, and hyperhidrosis. In the short-term studies, the highest DESS scores observed for desvenlafaxine groups occurred at first assessment after discontinuation of all active treatment (1.9-5.7). Desvenlafaxine 50- and 100-mg/day groups had significantly increased scores versus placebo (P values < or = 0.028). DESS scores increased significantly for patients discontinuing 12-week, OL desvenlafaxine 200 and 400 mg/day doses compared with those continuing desvenlafaxine (P values < or = 0.022). After the 6-month DB phase, DESS scores increased significantly compared with placebo for patients discontinuing 400 mg/day only (P = 0.029). In conclusion, cessation of desvenlafaxine use is associated with discontinuation symptoms after both short-term and long-term treatment.

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.

An evidence-based review of the clinical use of sertraline in mood and anxiety disorders

Sertraline is a selective serotonin reuptake inhibitor that has been used and studied extensively throughout the world and found to be safe and well tolerated in numerous patient populations, including those with either psychiatric and/or medical comorbidities. Randomized clinical trials have shown that it is an effective treatment for depressive and anxiety disorders and its efficacy is unaffected by psychiatric comorbidity. In non-comorbid patients, sertraline is effective for the acute treatment of major depressive disorders and prevention of relapse or recurrence. It is effective for acute treatment and longer-term management of social anxiety disorder, posttraumatic stress disorder,panic disorder, and generalized anxiety disorder. In adults and in pediatric patients, it is an effective short-term and long-term treatment for obsessive compulsive disorder.Sertraline has a good tolerability profile and has low fatal toxicity. In summary, sertraline is as effective as other antidepressants over a wide range of indications but may offer tolerability benefits as well as efficacy in patients with psychiatric and/or medical comorbidities and certain subtypes of depression.

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the pharmacological treatment of anxiety, obsessive-compulsive and post-traumatic stress disorders - first revision

In this report, which is an update of a guideline published in 2002 (Bandelow et al. 2002, World J Biol Psychiatry 3:171), recommendations for the pharmacological treatment of anxiety disorder, obsessive-compulsive disorder (OCD) and post-traumatic stress disorder (PTSD) are presented. Since the publication of the first version of this guideline, a substantial number of new randomized controlled studies of anxiolytics have been published. In particular, more relapse prevention studies are now available that show sustained efficacy of anxiolytic drugs. The recommendations, developed by the World Federation of Societies of Biological Psychiatry (WFSBP) Task Force for the Pharmacological Treatment of Anxiety, Obsessive-Compulsive and Post-traumatic Stress Disorders, a consensus panel of 30 international experts, are now based on 510 published randomized, placebo- or comparator-controlled clinical studies (RCTs) and 130 open studies and case reports. First-line treatments for these disorders are selective serotonin reuptake inhibitors (SSRIs), serotonin-noradrenaline reuptake inhibitors (SNRIs) and the calcium channel modulator pregabalin. Tricyclic antidepressants (TCAs) are equally effective for some disorders, but many are less well tolerated than the SSRIs/SNRIs. In treatment-resistant cases, benzodiazepines may be used when the patient does not have a history of substance abuse disorders. Potential treatment options for patients unresponsive to standard treatments are described in this overview. Although these guidelines focus on medications, non-pharmacological were also considered. Cognitive behavioural therapy (CBT) and other variants of behaviour therapy have been sufficiently investigated in controlled studies in patients with anxiety disorders, OCD, and PTSD to support them being recommended either alone or in combination with the above medicines.

Paroxetine: safety and tolerability issues

Paroxetine is a selective serotonin re-uptake inhibitor (SSRI) available in immediate release and controlled release (CR) formulations. Paroxetine is the most potent inhibitor of serotonin re-uptake among the now available SSRIs. Paroxetine has been approved for the treatment of major depressive disorder (MDD), obsessive-compulsive disorder, panic disorder (PD), generalised anxiety disorder, post traumatic stress disorder (PTSD), and social anxiety disorder (SAD) in adults, whereas paroxetine CR is approved for the treatment of MDD, SAD, PD and premenstrual dysphoric disorder in adults. The overall efficacy of paroxetine seems to be comparable to other SSRIs in the treatment of approved indications, although paroxetine treatment induces more sedation, constipation, sexual dysfunction, discontinuation syndrome and weight gain than other SSRIs. Recent data suggest that paroxetine treatment leads to increased rates of congenital malformations, although this evidence is not conclusive. Paroxetine and paroxetine CR are not indicated for use in the paediatric population and are categorised as Pregnancy Class D. In conclusion, whether the tolerability profile of paroxetine differs substantially from other new antidepressants (including other SSRIs) needs to be determined in adequately powered well-designed randomised controlled comparative clinical trials.

Is quetiapine a drug of abuse? Reexamining the issue of addiction

BACKGROUND

The abuse and diversion of pharmacological agents with CNS mechanisms of action is an important concern from governmental, regulatory, public health and safety perspectives. In recent years, there have been an increased number of reports concerning the abuse and diversion of quetiapine in forensic population and in individuals with histories of substance abuse.

OBJECTIVE

To better understand this surging pattern the available body of evidence was critically examined.

METHODS

A literature search from January 1991 to July 2008 restricting papers to English and using PUBMED and PsychInfo was performed.

RESULTS

Nine papers were identified. The content of these papers is discussed in light of recent research on drug abuse.

The medical treatment of obsessive-compulsive disorder and anxiety

Selective serotonin reuptake inhibitors (SSRIs) are first-line pharmacotherapy treatments for obsessive-compulsive disorder (OCD). Clomipramine is effective in OCD but associated with more adverse events. Typically, higher doses of antidepressants are required for OCD. Up to 50% of patients do not respond to initial treatment of OCD. Treatment options for nonresponders include augmentation of antidepressants with atypical antipsychotics, among other strategies. First-line treatments for anxiety disorders include SSRIs, serotonin norepinephrine reuptake inhibitors, and pregabalin. Tricyclic antidepressants are equally effective as SSRIs, but are less well tolerated. In treatment-resistant cases, benzodiazepines may be used when the patient does not have a history of dependency and tolerance. Other treatment options include irreversible and reversible monoamine oxidase inhibitors, the atypical antipsychotic quetiapine, and other medications. Cognitive-behavioral therapy has been sufficiently investigated in controlled studies of OCD and anxiety disorders and is recommended alone or in combination with the above medications.

A new look at the neonate's clinical presentation after in utero exposure to antidepressants in late pregnancy

OBJECTIVES

To identify symptoms in neonates exposed to antidepressants in late pregnancy and to propose a categorization of these symptoms to help clinical assessment of antidepressant effects in exposed neonates.

METHODS

Data were extracted retrospectively from maternal and neonatal hospital charts. A total of 73 neonates exposed to antidepressant and 73 nonexposed neonates were included. Neonatal symptoms reported in the literature to be related to antidepressant exposure were collected. Multiple logistic regression analysis was used to estimate the association of neonatal symptoms and antidepressant exposure. Factorial analysis was used to regroup the neonatal symptoms.

RESULTS

Increased risk of alertness alteration (odds ratio [OR], 37;95% confidence interval [CI], 8-174), altered muscular tone (OR,20; 95% CI, 5-71), feeding and GI problems (OR, 3.8; 95% CI, 1.7-8.1), tachypnea (OR, 2.5; 95% CI, 1.1-5.3), and neurological problems (8/73 vs 0/73; P = 0.006) were found. Three statistically significant clusters of symptoms associated with antidepressant exposures emerged from the factorial analysis. Two of these clusters were similar to those described in adults for serotonergic toxicity and antidepressant discontinuation syndrome while the other was closely related to neonatal immaturity.

CONCLUSIONS

Symptoms expressed in neonates exposed to antidepressants in late pregnancy could be gathered in three clusters. This grouping could be useful to develop a new tool helping in the assessment and care of the exposed newborns.

Hypotension following cardiac surgery associated with paroxetine and mirtazapine withdrawal

This case describes a 15-year-old patient who experienced postoperative hypotension following an elective Ross procedure for aortic stenosis/insufficiency. The patient was taking paroxetine and mirtazapine for depression which were held prior to surgery. Hypotension occurred approximately eight hours postoperatively and required vasopressor support. Upon reinitiation of antidepressant therapy, hypotension resolved and vasopressor support was discontinued. A year later the patient required conduit replacement, and antidepressant therapy was weaned off during the three weeks prior to surgery. No hypotension was observed following the second surgery. Paroxetine withdrawal has been well-documented within adult literature, but there is little information regarding mirtazapine withdrawal. Furthermore, cardiovascular effects have not been well-documented, and even less is known within the pediatric population. Withdrawal symptoms in these agents may be explained by cholinergic rebound and/or rapid decline in serum concentrations upon abrupt discontinuation. It may be reasonable to consider tapering antidepressants with short half-lives prior to elective surgery in which patients may not be able to take maintenance medications for more than 24 hours.

Limitations of current medical treatments for depression: disturbed circadian rhythms as a possible therapeutic target

The proportion of diagnosed depressives prescribed antidepressants has increased markedly over the last 20 years, mainly following the introduction of the selective serotonin reuptake inhibitors. However, currently available antidepressants have notable limitations, relating to their only moderate efficacy relative to placebo, relatively slow onset of action, possible withdrawal symptoms, and problems of compliance. Sleep disturbances are often used to identify newly presenting depressive patients, and may be part of a more general alteration of bodily rhythms. There are links between pharmacological treatments and circadian rhythms in depression, which might represent another, new option for the development of a therapeutic approach to depression treatment. Many antidepressants affect sleep, some are sedative, and others have been used specifically in severely insomniac depressives. Disturbances in circadian rhythms may be an integral part of depressive mechanisms, and normalising them via an innovative mechanism of antidepressant action may be a fruitful avenue in the search for improved antidepressant agents.

Depression in adults: drug and physical treatments

INTRODUCTION

Depression may affect up to 10% of the population, with half of affected people having recurrence of their symptoms. In mild to moderate depression, there is no reliable evidence that any one treatment is superior in improving symptoms of depression, but the strength of evidence supporting different treatments varies. In severe depression, only prescription antidepressants and electroconvulsive therapy are known to improve symptoms.

METHODS AND OBJECTIVES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments in mild to moderate and severe depression, and in treatment-resistant depression? Which interventions reduce relapse rates? We searched: Medline, Embase, The Cochrane Library and other important databases up to April 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 87 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: antidepressant drugs (tricyclic antidepressants [including low-dose tricyclic antidepressants], selective serotonin reuptake inhibitors, monoamine oxidase inhibitors, reboxetine, or venlafaxine), continuing prescription antidepressant drugs, electroconvulsive therapy, exercise, lithium augmentation, pindolol augmentation, St John's Wort.

Paroxetine: current status in psychiatry

Paroxetine is a selective serotonin reuptake inhibitor (SSRI) with antidepressant and anxiolytic properties. It is commercially available in both an immediate-release (paroxetine) and a controlled-release formulation (paroxetine CR). The latter product was developed to improve gastrointestinal tolerability. Paroxetine is the most potent inhibitor of the reuptake of serotonin among the available SSRIs. It has approved indications for the treatment of major depression, obsessive-compulsive disorder, panic disorder, generalized anxiety disorder, post-traumatic stress disorder and social phobia in adults. Paroxetine CR is approved for the treatment of major depression, social anxiety disorder, panic disorder and premenstrual dysphoric disorder in adults. While the overall efficacy of paroxetine appears to be comparable with other SSRIs in the treatment of major depression, it is approved for use in a wider variety of anxiety disorders than any other antidepressant. Long-term data suggest that paroxetine is effective in preventing relapse or recurrence of depression for up to 1 year. Limited data show that paroxetine maintains a therapeutic response over 1 year in obsessive-compulsive disorder and up to 6 months in panic disorder. The side-effect profile of paroxetine is largely similar to that of the other SSRIs, although paroxetine tends to be more sedating and constipating in some patients, perhaps due to its anticholinergic activity. The potential for discontinuation syndrome and weight gain appears to be slightly higher with paroxetine than with other SSRIs. This review focuses on the immediate release and controlled-release formulations of paroxetine. It summarizes the efficacy and tolerability data for both formulations, with a particular emphasis on paroxetine CR which was introduced in 2002. It also discusses emerging evidence in other clinical areas and recent data that have led to modifications in the safety profile of paroxetine.

Necrotizing enterocolitis associated with in utero and breast milk exposure to the selective serotonin reuptake inhibitor, escitalopram

A term neonate presenting with necrotizing enterocolitis following in utero and breast milk exposure to the newest serotonin selective reuptake inhibitor, escitalopram, is described.

Potential Medical and Surgical Complications of Serotonergic Antidepressant Medications

Serotonergic antidepressants are the most widely used group of antidepressant medications. Although generally considered to have a favorable adverse-effect profile, serotonergic antidepressants are associated with potentially dangerous medical complications, some of which have only recently become apparent to patients and clinicians. This article reviews the association of serotonergic antidepressants and the following medical complications: syndrome of inappropriate antidiuretic hormone secretion, bleeding, serotonin syndrome, serotonin-discontinuation syndrome, and adverse pregnancy and neonatal effects. Physicians need to remain aware of these potential medical complications and integrate this information into their clinical decision-making, informed-consent process, baseline assessment, and follow-up monitoring.

Pharmacotherapy of Mood Disorders and Treatment Discontinuation

Depression is the most frequent and costly problem in primary care, where most of these patients are seen and treated. In many countries, the public regard antidepressant drugs as 'addictive', partly because of the withdrawal symptoms that can occur when they are discontinued. Indeed, discontinuation (withdrawal) symptoms can follow the stoppage of almost all classes of antidepressants, including selective serotonin receptor inhibitors (SSRIs). This is important because they are widely regarded as drugs of choice for both depression and the anxiety disorders. But is this true withdrawal or merely rebound? The antidepressant discontinuation syndrome is characterised by the time-locked emergence of new, clearly defined and quantifiable signs and symptoms that ensue on stopping or reducing the dose of an antidepressant. Thereby, it meets the criteria for a withdrawal syndrome. The symptoms are not usually severe or protracted. SSRIs vary in their propensity to be associated with a discontinuation syndrome: paroxetine appears to be the most likely. Patients should be warned of the possibility of developing such a reaction, but reassured that it is usually mild and self limiting. Tapering the dose, if practicable, is worthwhile. In severe cases, temporary reinstatement of the SSRI and slower tapering may be necessary. Escalation of antidepressant dosage, or 'street abuse', is rare with antidepressants. The use of antidepressants is generally beneficial, and efforts should be made to optimise our current use of these drugs as well as encouraging the development of newer, better and innovative compounds. To this end, physicians should educate themselves and the public about discontinuation and withdrawal, so that these clinical features can be put in a realistic context.