Anticholinergic prophylaxis of acute haloperidol-induced acute dystonic reactions.

Young adults treated with a high potency neuroleptic such as haloperidol are at high risk of developing dystonic reactions. In this retrospective study, 15 of 16 young adult patients treated only with haloperidol had such reactions within 60 hours of beginning the drug, while none of the seven patients treated with haloperidol plus prophylactic benztropine mesylate developed dystonia. Although methodologic considerations limit the generalization of these results, they are consistent with other reports and suggest that initial anticholinergic prophylaxis is warranted in young patients treated with high potency antipsychotics. All dystonic reactions in these patients occurred within 2 1/2 days, justifying the consideration of discontinuing prophylaxis (which also causes side effects) after 1 week.