Determinants of the intravenous diazepam dose required for gastroscopy

Factors influencing the intravenous dose of diazepam required by 100 consecutive outpatients being prepared for peroral endoscopy were evaluated. Eleven patients reported a history of using 2 or more doses of benzodiazepine a week and required 0.48 +/- 0.1 mg/kg of diazepam compared with 0.30 +/- 0.02 mg/kg (P < 0.01) needed by 89 patients who reported less frequent or no use. The log (dose/kg) was negatively correlated with age (r = 0.51, P < 0.01), and the log dose was positively correlated with weight to a lesser degree (r = 0. 31, P < 0.01). In the larger group of patients who reported less than twice-weekly or no benzodiazepine use, no effect of alcohol use on dose was found. The dose was unrelated to sex. The findings emphasize the importance of individualizing intravenous doses of diazepam.