Melatonin is a naturally occurring hormone found in many animal tissues including the human brain. Melatonin in the human brain helps to regulate the sleep-wake cycle. An increase in the concentration of melatonin is a signal to the brain to go to sleep. Melatonin is sold over the counter in the United States as a dietary supplement which can be used as a sleep aid. Melatonin tends to be helpful to insomniacs who have difficulty falling asleep. Melatonin appears to be the most effective at helping people with Delayed Sleep Phase Syndrome. These are people who cannot fall asleep until late at night and have difficulty waking up early in the morning. There is less evidence that melatonin is helpful for other forms or insomnia. Melatonin is not very useful for insomniacs who suffer from early waking because it is rapidly eliminated from the bloodstream. The half-life of melatonin is only 35 to 50 minutes, Attempts have been made to remedy this problem by creating a controlled-release form of melatonin.
Ramelteon is a melatonin receptor agonist which is also used as a sleep aid. Ramelteon has proven quite helpful for people who have difficulty falling asleep. Ramelteon is only available by prescription.
To summarize: Regular melatonin is most helpful if you have difficulty falling asleep. It is not likely to be helpful if you have difficulty staying asleep or with quality of sleep. However, controlled-release melatonin has proven helpful for difficulty staying asleep or quality of sleep. Controlled-release melatonin may also be sold as sustained release, timed, release, or prolonged release melatonin.
Melatonin appears to be safe for adults with no notable side effects.
Consult your physician prior to use if you are pregnant, nursing or being treated for depression. Do not drive or operate heavy machinery while using melatonin. Not intended for children under 12. Drugs which are metabolized by the liver, including alcohol, may increase melatonin's sedative effect. Taking melatonin together with other sedatives may increase its sedative effect. For information about the interaction of melatonin with other drugs please consult your physician or visit http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-melatonin.html
For more information about sleep aids please visit our web page: Insomnia, Alcohol, and Sleep Aids.
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