Melatonin

ByLaura Shane-McWhorter, PharmD, University of Utah College of Pharmacy
Reviewed/Revised Mar 2024
VIEW PROFESSIONAL VERSION

sleep-wake cycle. Melatonin used in supplements can be derived from animals, but most is produced artificially. In some countries, melatonin is considered a medication and is regulated as such.

(See also Overview of Dietary Supplements.)

Claims for Melatonin

People use melatonin mostly to treat insomnia and to help minimize the effects of jet lag or of shift work. People who are traveling across time zones may take melatonin on the day or night of departure and for 2 to 4 nights after arrival. People who rotate work shifts may take melatonin before going to bed. Research is being conducted in using melatonin to resynchronize the sleep-wake cycle for people in the early phases of Alzheimer disease, as well as for seasonal affective disorder (feeling depressed during winter months).

Evidence for Melatonin

Evidence suggests that melatonin supplements can affect the sleep-wake cycle. Thus, melatonin supplements may help certain people with symptoms of jet lag or temporary insomnia and has been used for as long as 6 months. However, there is little evidence that melatonin effectively treats chronic insomnia.

Side Effects of Melatonin

Headache, dizziness, nausea, sleepiness, and transient depression may occur. Melatonin may increase existing depression. Whether melatonin is safe when used long-term is unknown. Melatonin is best taken under medical supervision, particularly when given to children. In people with epilepsy, melatonin may increase seizures. Melatonin may exacerbate autoimmune diseases. Also, melatonin may decrease fertility, and whether melatonin is safe in pregnancy or while breastfeeding is unknown.

Drug Interactions with Melatonin

Melatonin

Melatonin may enhance the sedative effects of certain medications such as benzodiazepines.

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Some medications may affect melatoninmelatoninmelatonin levels.

Recommendations for Melatonin

People with problems sleeping or who want to treat or prevent jet lag can try melatonin, but most, particularly those considering taking melatonin repeatedly, should consult with their doctor first. Melatonin

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  1. National Institutes of Health's National Center for Complementary and Integrative Health: Melatonin: What You Need To Know

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