A premarketing multicenter trial of lorazepam injection.

Before the introduction of lorazepam injection to the Canadian market, its usefulness and acceptability were assessed in an open multicenter study. Anesthesiologists in teaching hospitals across the country were asked to substitute lorazepam injection for their usual anxiolytic premedicant in ten patients and to complete a brief case report on each patient. The results from 360 patients showed that suitable preoperative sedation, accompanied by anxiolysis but without undue effects on arousability, was obtained in 88% of the patients prior to surgery. The adverse effect most often reported, accounting for 84% of the drug-related adverse reactions, was postoperative drowsiness, which highlighted the need to administer the drug at least two hours before surgery. The anesthesiologists found lorazepam injection to be a satisfactory premedicant, rating it excellent to good in 73% of the patients treated.