Midazolam versus hydroxyzine as intramuscular premedicant

A randomized, double-blind, placebo-controlled, study was carried out in which the effects of midazolam (0.08 mg.kg-1) and hydroxyzine (1.5 mg.kg-1), with or without atropine (0.4 mg) or hyoscine (0.4 mg) were compared as intramuscular premedicants. Midazolam produced quicker onset of action, greater anxiolysis for the first hour, greater amnesia, less local irritation and a higher overall rating by the patients. Drowsiness, while also greater after midazolam, was neither marked nor prolonged. Both drugs were given similar overall ratings by the anaesthetists who administered the anaesthetics. Neither drug produced systemic toxicity. Of the two drugs known to produce amnesia, midazolam had a more profound effect and had an earlier onset than hyoscine. Midazolam (0.08 mg.kg-1) shows good potential as an intramuscular premedicant, especially when anaesthetic induction occurs 30 to 60 minutes later. Hyoscine, but not atropine, enhances the effects of the sedative drugs.