Decreased extrapyramidal symptoms with intravenous haloperidol.

In a preliminary, prospective study, the intensity of extrapyramidal symptoms was rated in four patients receiving intravenous haloperidol and six patients receiving oral haloperidol. The raters were blind to the route of administration. In this pilot study, the first systematic evaluation of intravenous haloperidol and extrapyramidal symptoms, the patients receiving intravenous haloperidol experienced significantly (p less than .01) less intense extrapyramidal symptoms than did the patients receiving oral haloperidol. The literature on intravenous haloperidol is briefly reviewed, and possible explanations of the lower intensity of extrapyramidal symptoms with intravenous haloperidol in the patients studied are discussed.