Lorazepam for the treatment of psychotic agitation

A prospective, double-blind, randomized trial of midazolam versus haloperidol versus lorazepam in the chemical restraint of violent and severely agitated patients

OBJECTIVES

To determine if midazolam is superior to lorazepam or haloperidol in the management of violent and severely agitated patients in the emergency department. Superiority would be determined if midazolam resulted in a significantly shorter time to sedation and shorter time to arousal.

METHODS

This was a randomized, prospective, double-blind study of a convenience sample of patients from an urban, county teaching emergency department. Participants included 111 violent and severely agitated patients. Patients were randomized to receive intramuscular midazolam (5 mg), lorazepam (2 mg), or haloperidol (5 mg).

RESULTS

The mean (+/-SD) age was 40.7 (+/-13) years. The mean (+/-SD) time to sedation was 18.3 (+/-14) minutes for patients receiving midazolam, 28.3 (+/-25) minutes for haloperidol, and 32.2 (+/-20) minutes for lorazepam. Midazolam had a significantly shorter time to sedation than lorazepam and haloperidol (p < 0.05). The mean difference between midazolam and lorazepam was 13.0 minutes (95% confidence interval [95% CI] = 5.1 to 22.8 minutes) and that between midazolam and haloperidol was 9.9 minutes (95% CI = 0.5 to 19.3 minutes). Time to arousal was 81.9 minutes for patients receiving midazolam, 126.5 minutes for haloperidol, and 217.2 minutes for lorazepam. Time to arousal for midazolam was significantly shorter than for both haloperidol and lorazepam (p < 0.05). The mean difference in time to awakening between midazolam and lorazepam was 135.3 minutes (95% CI = 89 to 182 minutes) and that between midazolam and haloperidol was 44.6 minutes (95% CI = 9 to 80 minutes). There was no significant difference over time by repeated-measures analysis of variance between groups in regard to changes in systolic and diastolic blood pressure (p = 0.8965, p = 0.9581), heart rate (p = 0.5517), respiratory rate (p = 0.8191), and oxygen saturation (p = 0.8991).

CONCLUSIONS

Midazolam has a significantly shorter time to onset of sedation and a more rapid time to arousal than lorazepam or haloperidol. The efficacies of all three drugs appear to be similar.

Chemical restraint for the agitated patient in the emergency department: lorazepam versus droperidol

Patients presenting to the emergency department with acute agitation frequently require physical and chemical restraint. To determine the efficacy of lorazepam vs. droperidol, we conducted a prospective, randomized study of violently agitated patients requiring chemical restraint. Patients were randomized to receive either lorazepam or droperidol i.v. A six-point sedation scale was used. Sedation scores were recorded at time 0, 5, 10, 15, 30, and 60 min. Vital signs were compared at time 0 and at 60 min. Repeat dosages of each drug could be given at 30 min. Toxicology screen, ethanol and creatinine phosphokinase levels were obtained. A total of 202 patients were evaluated. One hundred patients received lorazepam and 102 patients received droperidol. Agitation was attributed to methamphetamine toxicity in 146 patients (72%), cocaine toxicity in 28 (14%), psychiatric illness in 20 (10%), and ethanol withdrawal in 8 (4%). Ethanol intoxication was present in 98 patients (49%). Both drugs had similar sedation profiles at 5 min. Patients receiving droperidol had significantly lower sedation scores at times 10, 15, 30, and 60 than lorazepam. More repeat doses of lorazepam were given (40) than droperidol (8) at 30 min. We conclude that droperidol produces a more rapid and better sedation than lorazepam at the doses used in this study in agitated patients requiring chemical restraint. Lorazepam is more likely to require repeat dosing than droperidol. Methamphetamine toxicity was present in the majority of patients in this study.