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Medically reviewed by Last updated on May 5, 2023.

What are other common names?

  • 5-Methoxy-N-Acetyltryptamine
  • Circadin
  • MEL
  • Melatonia
  • MLT
  • N-Acetyl-5-Methoxytryptamine
  • Pineal Hormone

What is this product used for?

Melatonin is used in some people to help regulate sleep. This may be people who travel a lot or who work different shifts. This may also be people who have certain sleep disorders where they have problems falling asleep. Melatonin may help improve certain types of pain in some people. Melatonin may help improve some side effects caused by certain drugs. It may also help to lower side effects from chemotherapy.

What are the precautions when taking this product?

  • Always check with your doctor before you use a natural product. Some products may not mix well with drugs or other natural products.

  • This product may interfere with some lab tests. Be sure to talk with your doctor about this and all drugs you are taking.

  • Be sure to tell your doctor that you take this product if you are scheduled for surgery or tests.

  • Be sure to tell your doctor if you are pregnant, plan on getting pregnant, or are breastfeeding. You will need to talk about the benefits and risks of using this natural product.

  • This product may cause you to be sleepy. Take extra care driving and doing tasks that you need to be alert for.

  • Avoid beer, wine, mixed drinks (alcohol), and marijuana while taking this product.

  • Take extra care if you are taking drugs that make you drowsy or help you to sleep. These are drugs like lorazepam, phenobarbital, zolpidem, or diphenhydramine.

  • Take extra care if you are at a high risk for infection. This includes people who have had a transplant, are on chemo, or have an autoimmune disease.

  • Take extra care and check with your doctor if you have:

    • Autoimmune disease

    • Blood pressure problems

    • Seizures

    • Low mood

    • Dementia

    • Diabetes

    • Cancer

  • Keep hard candies, glucose tablets, liquid glucose, or juice on hand for low blood sugar.

What should I watch for?

  • Upset stomach

  • Dizziness

  • Daytime sleepiness

  • Bed wetting

  • Low mood

  • Irritability or agitation

  • Trouble sleeping or nightmares

When do I need to call the doctor?

  • Signs of a very bad reaction. These include wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat. Go to the ER right away.

  • Signs of low blood sugar. These include hunger, dizziness, shaking, a fast heartbeat, confusion, or sweating.

  • Very bad throwing up

  • Very bad loose stools

  • Very bad headache

  • Bruising or bleeding that is not normal

Where can I learn more?

National Center for Complementary and Integrative Health

Last Reviewed Date


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