EXACERBATION OF POSTURAL TREMOR WITH EMERGENCE OF PARKINSONISM AFTER TREATMENT WITH NEUROLEPTIC DRUGS

Neuroleptic medication in three patients with prior isolated postural arm tremor led to a conspicuous deterioration; the postural tremor inc reased in amplitude, tremor appeared at rest, and other signs of mild parkinsonism developed. Withdrawal of neuroleptic drugs led to improve ment in tremor and disappearance of parkinsonism. Positron emission to mography showed no reduction in uptake of [F-18]dopa into nigrostriata l terminals suggesting that these patients did not have Parkinson's di sease. Neuroleptic drugs can convert postural essential arm tremor int o that characteristic of Parkinson's disease in patients with no evide nt nigrostriatal lesion.