Abnormal involuntary movements induced by anticholinergic therapy.

Abstract

Six patients developed abnormal involuntary movements during treatment with centrally active anticholinergic agents. Four of the patients had Parkinson's disease, and two had non-parkinsonian tremors. In all the cases the involuntary movements comprised bucco-linguo-masticatory dyskinesias, and in two, involuntary movements of the limbs as well. The dyskinesias subsided following discontinuation of the anticholinergics. In the four parkinsonian patients anticholinergic therapy was resumed with a different substance with the result that the dyskinesias reappeared, but subsided again after discontinuation. As other possibilities could be excluded, the dyskinesias observed may probably be considered to have been induced by the anticholinergic therapy.