Pharmacotherapy in Patients with Drug-induced Parkinsonism: A Case Series

Drug-induced Parkinsonism develops in a number of patients with schizophrenia or schizo-affective disorders. Conventionally, anti-parkinsonism drugs, such as levodopa and dopamine agonists have been avoided due to their potential to result in an increase in psychotic symptoms, hallucinations and behavioral disturbance.

We present ten cases series of drug-induced Parkinsonism in whom a trial of anti-parkinsonism medications administered commenced with good effect. In particular, there was no deterioration in psychotic symptoms. A number of cases had asymmetrical signs, suggesting that these patients had a component of idiopathic Parkinson’s disease in addition to long standing drug-induced Parkinsonism.

The diagnosis of idiopathic Parkinson’s disease on clinical grounds is often difficult in patients who have been on or are currently on an anti-psychotic drug. A trial of levodopa or a dopamine agonist is worth considering, albeit cautiously. In our series of cases a relapse or exacerbation of psychotic symptoms did not occur after commencing levodopa and dopamine agonists.