To establish the frequency of
drug-induced
parkinsonism (DIP) and the drugs responsible for this side-effect we reviewed the database of our
Movement Disorders Unit during the first 4 years of its use. The diagnostic criteria for DIP included: (1) the presence of two or more cardinal symptoms of
parkinsonism, (2) an absence of parkinsonian symptoms before the exposure to the offending
drug, (3) a disappearance or significant improvement in
parkinsonism after withdrawal of the offending
drug, (4) no better explanation for the
parkinsonism. One-hundred and five patients fulfilled the diagnostic criteria for DIP (16.3% of total patients referred and 33.8% of patients with
parkinsonian syndromes).
Drug-induced
parkinsonism was related to 1, 2, 3, 4, 5 and 7 drugs in 62, 30, 9, 1, 2 and 1 patients, respectively. The most frequently offending drugs were:
calcium-channel blockers (61 cases),
antipsychotic drugs (29 cases),
thiethylperazine (18 cases),
clebopride (14 cases), and
sulpiride (10 cases). When compared with
idiopathic Parkinson's disease patients, DIP patients were predominantly female and showed an older age at the onset of parkinsonian signs. Parkinsonian signs only disappeared completely in 41 patients (39.0%).
IN CONCLUSION: