The quality of evidence is downgraded by study limitations (selective outcome reporting).
Melatonin is suggested as a safe alternative to benzodiazepines when preanaesthetic anxiolytic drugs are needed.
A Cochrane review [Abstract] 1 included 12 randomised controlled trials (RCTs) with a total of 774 subjects. The RCTs assessed melatonin for treating preoperative anxiety, postoperative anxiety or both. Four of the 12 studies compared melatonin, placebo and midazolam, whereas the remaining eight studies compared melatonin and placebo only. Eight out the 10 studies that assessed the effect of melatonin (3-14 mg) on preoperative anxiety using a visual analogue scale (VAS) (ranging from 0 to 100 mm, higher scores indicate greater anxiety) showed a reduction compared to placebo. The reported estimate of effect (relative effect -13.36, 95% confidence interval (CI) -16.13 to -10.58) was based on a meta-analysis of seven studies (483 subjects). Two studies did not show any difference between melatonin and placebo. Two studies comparing melatonin (5 mg and 0.05-0.2 mg/kg) with midazolam (15 mg and 0.05-0.2 mg/kg; 3.5-15 mg) using a VAS found no evidence of a difference in preoperative anxiety between the two groups (relative effect -1.18, 95% CI -2.59 to 0.23).
Date of latest search: 2013-04-19
Primary/Secondary Keywords