Does melatonin work for sleep?

It helps most with circadian problems — jet lag, shift work, delayed sleep phase — rather than classic insomnia. Low doses (0.5–3 mg) taken a few hours before target bedtime work better than large doses at bedtime.

Melatonin is a timing signal rather than a sedative. It works best for jet lag, shift work and delayed sleep phase, and poorly for classic insomnia.

Low doses of 0.5-3 mg taken 2-3 hours before target bedtime are more effective than 5-10 mg at bedtime. Discuss before use in children, pregnancy or with other medication.