The New York Times published a guide on how to take melatonin for circadian rhythm disorders and insomnia.
First, melatonin supplements are useful when you have a circadian rhythm disorder such as jet lag or sleep pattern disruptions resulting from shift work. When used to treat these conditions, melatonin supplements signal to the brain that it is nighttime and the body should start winding down.
In these instances, said Dr. Bhanu Kolla, an associate professor in psychiatry and psychology and a consultant in sleep medicine at the Center for Sleep Medicine at the Mayo Clinic, it is best to use low doses of melatonin supplements. Consult with a doctor if you have any questions or concerns.
The second use for melatonin supplements is when you have difficulty falling asleep and staying asleep. Over all, Dr. Kolla said, melatonin supplements, if taken before bedtime, reduce the time to fall asleep. In one study published in PLOS One, people who took melatonin supplements fell asleep seven minutes faster and increased overall sleep time by eight minutes. Researchers found that overall sleep quality was improved too.
For those addressing sleep regulation issues, experts suggest taking 0.5 milligrams two to three hours before bed. For people with insomnia who need help falling asleep, you can take 5 milligrams 30 minutes before bedtime.