The one reasonably common adverse effect of acute IM Haldol administration is a dystonic reaction. Dystonic reactions involve involuntary muscle contractions usually in the neck, shoulders or face, but also elsewhere. It can also manifest as akesthesia, which can be thought of as a case of restless legs from hell. We are not talking here about Tardive Dyskinesia. Tardive Dyskinesia is also involuntary muscle contractions but these occur after years of neuroleptic medication use and are irreversible. Acute dystonic reactions are easily reversible, using an antihistamine, like Benadryl. Unlike tardive dyskinesia, dystonic reactions are a nuisance, trivial and easily treated.
We considered 27 studies from the 2007 search. In this update we considered a further 38 studies from the 2013 search, and two in the 2014 search. We identified one RCT of moderate quality with low risk of bias overall which met the inclusion criteria for this update, comparing ABH (Ativan®, Benadryl®, Haldol®) gel, applied to the wrist, with placebo for the relief of nausea in 22 participants. ABH gel includes haloperidol as well as diphenhydramine and lorazepam. The gel was not significantly better than placebo in this small study ; however haloperidol is reported not to be absorbed significantly when applied topically, therefore the trial does not address the issue of whether haloperidol is effective or well-tolerated when administered by other routes (. by mouth, subcutaneously or intravenously). We identified one ongoing trial of haloperidol for the management of nausea and vomiting in patients with cancer, with initial results published in a conference abstract suggesting that haloperidol is effective for 65% of patients. The trial had not been fully published at the time of our review . A further trial has opened, comparing oral haloperidol with oral methotrimeprazine (levomepromazine) for patients with cancer and nausea unrelated to their treatment, which we aim to include in the next review update.