Tardive dyskinesia and anticholinergic drugs. A critical review of the literature.

The prevalent theory of tardive dyskinesia indicates that this condition may result from an imbalance of the cholinergic-dopaminergic system. Thus, claims have been made that anticholinergic drugs may increase the incidence of tardive dyskinesia and the severity of the established form of this syndrome. The author reviews the literature with these two claims in mind. While the studies published do not indicate that the incidence of tardive dyskinesia is increased by the addition of anticholinergic medication, there is ample evidence to indicate that anticholinergic drugs may increase the severity of established tardive dyskinesia. Thus, it is recommended that anticholinergic drugs should be discontinued when a patient develops tardive dyskinesia.