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Melatonin side effects: What are the risks?

Medically reviewed by Drugs.com. Last updated on Oct 28, 2022.

The hormone melatonin plays a role in the sleep-wake cycle. Natural levels of melatonin in the blood are highest at night. Some research suggests that melatonin supplements might be helpful in treating sleep disorders, such as delayed sleep phase. They also may provide some relief from insomnia and jet lag.

Melatonin is generally safe for short-term use. Unlike with many sleep medications, with melatonin you are unlikely to become dependent on it, have less response to it after repeated use or experience a hangover effect.

The most common melatonin side effects include:

Other, less common melatonin side effects might include:

Because melatonin can cause drowsiness, don't drive or use machinery within five hours of taking it.

Melatonin supplements can interact with some types of medicine, including:

Before you take melatonin supplements, check with your health care provider first, especially if you have any health conditions or if you are taking other medicine. Melatonin supplements you can buy without a prescription vary widely in the amount of melatonin they contain. Your provider can help you decide if melatonin is right for you and, if so, which one is a good choice for your situation.

And keep in mind that, as with any supplement, melatonin shouldn't be the first or only remedy you use to try to resolve a health concern such as insomnia. It needs to be coupled with lifestyle choices that create a solid foundation for good health. That includes fundamentals such as good nutrition, daily exercise, a daily mind-body practice, good sleep hygiene, social connectedness and spirituality.

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