The study used the United Parkinson's Disease Scale to compare
parkinsonian signs and symptoms among 19 patients in long-term neuroleptic
therapy who had a history of cocaine abuse with those among 24 similar
patients with no history of cocaine use. There was no significant
difference between the two groups' scores. The results suggest that chronic
cocaine abuse is not a risk factor for parkinsonism among subjects in
long-term neuroleptic therapy.