Reports of withdrawal syndrome with the use of SSRIs: a case/non-case study in the French Pharmacovigilance database

The SSRIs can be associated with withdrawal reactions and the objective of this study is to test the existence of an association between reports of withdrawal syndromes with the selective serotonin re-uptake inhibitors in the French spontaneous reports database. All reactions are coded according to the WHO ART dictionary. Cases are reports of reactions of interest (withdrawal syndrome). Non-cases are all reports of reactions other than those being studied. We calculated the odds ratio (OR) as the ratio of the odds of the association of reports of withdrawal syndrome with SSRIs in cases and non-cases. SSRIs are clearly associated with a higher risk of withdrawal syndrome (OR: 5.05, 95% CI: 3.81-6.68) and in particular with venlafaxine and paroxetine (OR: 12,16, 95% CI: 6.17-23.35 and OR: 8.47, 95% CI: 5.63-12.65, respectively). The risk of withdrawal reactions appears to be greater with short half-life drugs such as paroxetine and venlafaxine. The precise mechanisms have not been identified. Copyright (C) 2002 John Wiley Sons, Ltd.