A re-evaluation of the anxiolytic properties of intramuscular midazolam.

The observed effect of midazolam on anxiety is equivocal in part because previous studies have not ruled out pre-treatment differences in anxiety scores between patients who received midazolam and those who did not (controls). This study re-examines the anxiolytic effect of premedication with intramuscular midazolam using a sample size calculated to be of sufficient size to rule out population differences as a variable affecting treatment results. In the midazolam group (n = 49) anxiety scores were determined prior to administration of midazolam 0.07 mg/kg intramuscularly, and again 60 minutes later. In the control group (n = 47) anxiety scores were determined prior to intramuscular injection of a similar volume of matching placebo (midazolam vehicle), and again 60 minutes later. No differences in anxiety scores between groups either before treatments or 60 minutes after treatments were observed. Within both groups, anxiety scores at 60 minutes were no different from pre-treatment scores. In this study midazolam did not produce a statistically significant decrease in pre-operative anxiety scores at 60 minutes following intramuscular administration.