Extrapyramidal reactions following treatment with antidepressants: Results of the AMSP multinational drug surveillance programme

Objectives: Extrapyramidal symptoms (EPS) are a common adverse effect of antipsychotics. However, there are case reports describing EPS following treatment with antidepressants. It is not fully understood how antidepressants cause EPS, but a serotonergic input to dopaminergic pathways is a probable mechanism of action. Methods: Data from a multicenter drug-surveillance programme (AMSP, ‘drug safety in psychiatry’) which systemically documents severe drug reactions during psychiatric inpatient admissions, were reviewed to assess for EPS associated with antidepressant treatment. We identified 15 such cases, which were studied to detect similarities and to characterise risk factors. Results: We report on 15 patients with EPS following antidepressant-therapy between 1994 and 2016. EPS frequently occurred with selective serotonin reuptake inhibitor (SSRI) treatment alone (7/15 cases) or concomitant SSRI treatment (6/15 cases). EPS were most frequent with escitalopram-treatment (5 cases). The most common EPS was atypical dyskinesia (6/15 cases) followed by akathisia (4/15 cases). The mean age of onset for EPS was 54.93 years (SD 17.9). EPS occurred at any dosage and equally often in men and women. Conclusions: Our results highlight the possibility of EPS as an important, although uncommon, adverse effect of antidepressants. Clinicians should beware of this adverse effect and monitor early warning signs carefully.