More cases of paroxetine withdrawal syndrome

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.

Comparative effects of 15 antidepressants on the risk of withdrawal syndrome: A real-world study using the WHO pharmacovigilance database

BACKGROUND

While case reports and clinical trials reported withdrawal syndrome after reduction and/or discontinuation of antidepressant drugs, no large study has been conducted to compare the risk between the different antidepressants.

METHODS

Using data recorded from January 1st, 1988, and December 31st, 2020 in VigiBase®, the World Health Organization's Global Individual Case Safety Reports database, we performed disproportionality analysis to investigate the risk of reporting withdrawal syndrome in patients treated by short half-life antidepressants compared with patients treated by long half-life antidepressants. In addition, we aimed to better inform clinical practice by comparing 15 antidepressants for the risk of reporting withdrawal syndrome.

RESULTS

Among the 338,498 reports with antidepressants of interest, we found 15,507 cases of withdrawal syndrome. Short half-lives antidepressants were associated with an increased risk of reporting a withdrawal syndrome compared to long half-life antidepressants (ROR 5.38; 95% CI 5.16-5.61). The risk was higher for 18-44 years old (ROR 6.88; 95% CI 6.17-7.62), women (ROR 1.38; 95% CI 1.33-1.43) and patients treated with Paroxetine, Desvenlafaxine, Venlafaxine and Duloxetine.

LIMITATIONS

The limitations of this study stem from the case-reporting process.

CONCLUSIONS

This large observational study in a real-world setting suggests that the use of short half-life antidepressants increases the risk of reporting withdrawal syndrome compared to long half-life antidepressants. Among the most common antidepressants, paroxetine and serotonin-noradrenaline reuptake inhibitors are associated with a greater risk of reporting withdrawal syndrome, while agomelatine and vortioxetine present a lower risk. Additional studies are needed to corroborate our results.

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.

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.

Did intense adverse media publicity impact on prescribing of paroxetine and the notification of suspected adverse drug reactions? Analysis of routine databases, 2001-2004

AIM

To document the impact on clinical practice in England of media attention around possible adverse effects of paroxetine.

DESIGN

Analysis of national selective serotonin reuptake inhibitor (SSRI) prescribing trends and yellow-card adverse drug reaction reports, 2001-2004.

RESULTS

From a steady state in 2001, paroxetine prescribing declined sharply from April 2002, coinciding with a USA regulatory action; the subsequent decline in paroxetine prescribing was 1.87% per month (95% confidence interval - 2.06, -1.68). Other SSRI prescribing increased by 1% per month until a major UK review of SSRIs in children in December 2003, after which prescribing plateaued. Media publicity was associated with short-term peaks in yellow-card reports related to paroxetine.

CONCLUSION

Falls in paroxetine and other SSRI prescribing in the UK coincided, respectively, with regulatory communications from the USA and the UK, but associations may have noncausal or other explanations. Reports of adverse reactions to paroxetine appeared to increase after adverse media publicity about the drug.

Discontinuation symptoms: comparison of brief interruption in fluoxetine and paroxetine treatment

Abrupt interruption or cessation of selective serotonin reuptake inhibitor (SSRI) treatment may result in discontinuation or treatment interruption symptoms. Recent reports suggested these symptoms occur more frequently with shorter half-life SSRIs. Previous studies indicated a 5-8-day treatment interruption resulted in fewer discontinuation-emergent adverse events in fluoxetine-treated patients than in paroxetine-treated patients. This study examines the effects of shorter treatment interruption (3-5 days), as would occur if patients miss just a few doses of medication. Patients successfully treated for depression with fluoxetine or paroxetine underwent treatment interruption in a double-blind fashion. Treatment interruption-emergent symptoms were assessed using the Discontinuation-Emergent Signs and Symptoms checklist. Other assessments included the Montgomery-Asberg Depression Rating Scale, Clinical Global Impressions-Severity scale and a social functioning questionnaire. Of 150 patients enrolled, 141 completed the study. Following treatment interruption, fluoxetine-treated patients experienced fewer treatment interruption-emergent events than did paroxetine-treated patients. The paroxetine treatment group also experienced significant increases in depressive symptoms, clinical global severity scores and difficulty in social functioning; the fluoxetine treatment group did not. These results are consistent with reports suggesting abrupt interruption of treatment with paroxetine is more often associated with somatic and psychological symptoms than is abrupt interruption of fluoxetine. Patients treated with fluoxetine appeared to be protected by its longer half-life.

Discontinuation syndrome in dysthymic patients treated with selective serotonin reuptake inhibitors: a clinical investigation

OBJECTIVE

Many authors have reported discontinuation symptoms associated with selective serotonin reuptake inhibitors (SSRIs). The aim of this study was to investigate the incidence and characteristics of the discontinuation syndrome in patients who stopped treatment with the SSRIs paroxetine and fluoxetine under the usual conditions of clinical practice, and to identify clinical predictors of the syndrome.

METHODS

Ninety-seven outpatients who received an initial diagnosis of dysthymic disorder, who responded to >or=8 weeks treatment with paroxetine (n = 52) or fluoxetine (n = 45), and who discontinued the SSRI according to their psychiatrist's instructions were included. They were assessed at the time of discontinuation using a semi-structured interview for clinical and treatment characteristics, the Hamilton Depression Rating Scale (HAM-D) and the Montgomery-Asberg Depression Rating Scale (MADRS). Patients were then assessed 4 weeks later using a checklist for discontinuation symptoms, a semi-structured interview for discontinuation symptom characteristics, and the HAM-D and the MADRS.

RESULTS

A discontinuation syndrome was found in 26 patients (26.8% of our sample); of this group, 22 patients (84.6%) had received paroxetine, and 4 patients (15.4%) had received fluoxetine. The mean time at onset of symptoms was 2 days after drug discontinuation and the mean duration was 5 days. The statistical comparison between the groups with and without a discontinuation syndrome found two significant differences - a discontinuation syndrome was more common in patients treated with paroxetine and in patients with an earlier onset of dysthymic disorder. Multiple regression analysis confirmed that these two factors were related to the duration of discontinuation symptoms, while the number of symptoms was associated with three factors, including use of paroxetine, age at onset of dysthmia and female gender.

CONCLUSIONS

A discontinuation syndrome is common after treatment with SSRIs is stopped in patients with dysthymia, and it appears to be more common in patients receiving paroxetine than in those receiving fluoxetine. The syndrome is related both to drug and clinical characteristics. The features of the syndrome in patients with different Axis I diagnoses should be compared in further investigations.

Antidepressant Discontinuation Syndromes

Discontinuation symptoms are recognised with tricyclic antidepressants, monoamine oxidase inhibitors, selective serotonin reuptake inhibitors (SSRIs) and miscellaneous antidepressants. A wide variety of symptoms have been described, differing somewhat between antidepressant classes, and several symptom clusters or discontinuation syndromes appear to exist. A common feature is onset within a few days of stopping the antidepressant or, less commonly, reducing the dosage. Discontinuation syndromes are clinically relevant as they are common, can cause significant morbidity, can be misdiagnosed leading to inappropriate treatment and can adversely effect future antidepressant compliance. Preventative strategies include tapering antidepressants prior to stoppage and educating patients and healthcare professionals to ensure that antidepressants are taken consistently and not stopped abruptly. Most reactions are mild and short-lived and require no treatment other than patient reassurance. Severe cases can be treated symptomatically or the antidepressant can be reinstated before being gradually withdrawn. Reinstatement usually leads to symptom resolution within 24 hours. Some individuals require very conservative tapering schedules to prevent the re-emergence of symptoms. With SSRIs and venlafaxine another strategy to consider is switching to fluoxetine, which may suppress the discontinuation symptoms, but which has little tendency to cause such symptoms itself. Neonatal discontinuation symptoms can follow maternal use of antidepressants during pregnancy and possibly breast feeding. The patient and doctor must take this into consideration when making prescribing decisions. Discontinuation symptoms have received little systematic study with the result that most of the recommendations made here are based on anecdotal data or expert opinion. Research is needed to provide a firm evidence base for future recommendations.

The SSRI discontinuation syndrome

A characteristic selective serotonin reuptake inhibitor (SSRI) discontinuation syndrome appears to exist. It is usually mild, commences within 1 week of stopping treatment, resolves spontaneously within 3 weeks, and consists of diverse physical and psychological symptoms, the commonest being dizziness, nausea, lethargy and headache. SSRI reinstatement leads to resolution within 48 h. A transient stage of serotonin dysregulation appears central to causation with pharmacokinetic and pharmacodynamic differences accounting for the variation in incidence between the SSRIs. Discontinuation reactions are clinically relevant due to the associated morbidity, the potential for misdiagnosis and inappropriate treatment and because they may impair future antidepressant compliance. To minimize incidence, SSRIs, like other antidepressants, should be withdrawn gradually. Provisional diagnostic criteria for the SSRI discontinuation syndrome are proposed. Prospective studies are required to investigate the syndrome, particularly its effects on patient care.

Discontinuation symptoms with nefazodone

OBJECTIVE

We report a patient who developed discontinuation symptoms following nefazodone cessation.

CLINICAL PICTURE

The patient experienced nausea, vomiting, diarrhoea, ataxia, insomnia, marked agitation, headache and flu-like symptoms.

TREATMENT

She was reluctant to recommence nefazodone and was symptomatically treated with oxazepam.

OUTCOME

The patient recovered completely in 10 days.

CONCLUSIONS

Nefazodone discontinuation can result in withdrawal symptoms and therefore needs to be tapered gradually. Those who have experienced discontinuation symptoms with other antidepressants in the past may be at increased risk.

Selective serotonin reuptake inhibitors in the treatment of affective disorders--III. Tolerability, safety and pharmacoeconomics

The clinical use of tricyclic antidepressants (TCAs) is often complicated by toxicity and safety problems due to their effects on multiple mechanisms of action, many of which are unnecessary for therapeutic effect. The development of the selective serotonin reuptake inhibitors (SSRIs), with their selective mode of action, has resulted in a class of antidepressant drugs possessing an improved side-effect profile, while retaining good clinical efficacy. Their introduction into clinical practice has led to enhanced patient compliance with antidepressant therapy and the ability to maintain treatment over longer periods of time at an adequate therapeutic dose. Although, as a result of their selective action, side-effects associated with SSRI therapy are minimised, distinct variations between individual SSRIs in terms of their tolerability profiles have been observed. The wealth of clinical data now available has revealed differences in their potential to cause psychiatric and neurological side-effects, dermatological reactions, anticholinergic side-effects, changes in body weight, sexual dysfunction, cognitive impairment, discontinuation reactions and drug-drug interactions. Patients who suffer from concomitant depression and physical illness may experience different tolerability profiles, in addition to the greater likelihood that they will be receiving concomitant medications with the potential for pharmacokinetic drug-drug interactions with coadministered SSRI therapy. In addition, the safety margin of SSRIs in overdose may vary within the group. Knowledge of the differences that exist among the SSRIs in respect of tolerability and safety will aid physicians in the selection of the most beneficial treatment strategy for their patients. A successful clinical outcome leads to a reduced economic burden for the patient, their family and the healthcare services. Thus, pharmacoeconomic considerations are also important in choosing antidepressant therapy. The SSRIs, despite relatively higher prescription costs, have been demonstrated to be a more cost-effective option than the TCAs. Furthermore, there is evidence that the emerging clinical differences between SSRIs may translate into significantly different economic outcomes within the group.