Movement disorders induced by drugs: experience at a pharmaco-vigilance center over five years

The present retrospective study investigates the characteristics of drug-induced movement disorders notified to a Regional Drug Surveillance Centre. Among 4000 general side effects spontaneously reported to the Centre between 1989 and 1993, 122 were drug-induced movement disorders. Drug-induced parkinsonism (40 per cent) was mainly due to antidopaminergic agents (neuroleptics but also antiemetics or calcium channel blockers). Acute dyskinesia and dystonia (25 per cent) as well as tardive dyskinesia (14 per cent) involved mainly neuroleptics or antiemetics. Non-parkinsonian tremors (11 per cent) were related mostly to tricyclic antidepressants. Involvement of other less often suspected drugs (non-imipramine antidepressants, cardiac or hypolipidaemic drugs, etc) is discussed.