Parkinsonism associated with calcium channel blockers: a prospective follow-up study.

Parkinsonism is a well-known side effect of some calcium channel blockers (CCB). Its long-term evolution, however, is unknown. To clarify this issue, we performed a prospective follow-up study involving 32 patients diagnosed with CCB-induced parkinsonism. After the baseline examination, the CCB were discontinued and serial evaluations were carried out according to the same protocol. Despite a global improvement, cognitive and mood disturbances subsided slowly, and tremor persisted in most patients. After 18 months of CCB withdrawal, 44% of patients had depression, 88% had tremor, and 33% still had criteria for diagnosis of parkinsonism. During the survey, only three patients were found to be fully recovered. The improvement of some clinical symptoms was related to age: Patients younger than 73 years recovered better than older patients did. Our data indicate that CCB-induced parkinsonism is not the benign condition previously thought, and suggest an age-related prognosis of this entity.