Diazepam and lorazepam for intravenous surgical premedication.

Diazepam, 10 and 20 mg, and 2 and 4 mg lorazepam were studied as intravenous surgical premedicants in 120 patients. Relief of anxiety, sedation, patient acceptance, lack of recall, and side effects were the variables evaluated. Both diazepam and lorazepam proved to be excellent surgical premedicants. The basic difference between the two drugs is temporal. Both medications produce similar relief of anxiety, sedation, patient acceptance, and lack of recall. The clinical effects of intravenous diazepam peaks in 2 to 3 minutes and diminishes thereafter. Intravenous lorazepam has a latent period of 8 to 15 minutes, with increasing effects at 15 to 30 minutes.