MOVEMENT-DISORDERS ASSOCIATED WITH THE SEROTONIN SELECTIVE REUPTAKE INHIBITORS

Background: To review the case reports and case series of movement dis orders ascribed to the use oi serotonin selective reuptake inhibitors (SSRIs). Method: Reports of SSRI-induced extrapyramidal symptoms (EPS) in the literature were located using a MEDLINE search and review of b ibliographies. Results; Among the 71 cases of SSRI-induced EPS reporte d in the literature, the mast common side effect Was akathisia (45.1%) , followed by dystonia (28.2%), parkinsonism (14.1%), and tardive dysk inesia-like states (11.3%). Among patients with Parkinson's disease tr eated with SSRIs, there were 16 cases of worsening parkinsonism. Patie nts who developed dystonia, parkinsonism. or tardive dyskinesia were o lder on average than patients with akathisia: 67.6% of affected patien ts were females. Fluoxetine, the most commonly prescribed SSRI to date , was implicated in 53 (74.6%) of cases of SSRI-induced EPS. Several r eports (57.7%) were confounded by the concomitant use. of other medica tions that can contribute to the development of EPS. Conclusion: SSRI- induced EPS are probably related tu agonism of serotonergic input to d opaminergic pathways within the CNS, Several patient-dependent and pha rmacokinetic variables may determine the likelihood that EPS will emer ge. Although these side effects are infrequent, clinicians should be a lert to the possibility of their occurrence.