Home » Patients » Melatonin
October 2020 |  Reviewed by:  Shelley Hershner, MD and Andrea Matsumura, MD

What is melatonin?

Melatonin is a hormone that is naturally produced by your body and plays an important role in sleep. It helps regulate your sleep-wake cycle by signaling to your body when the time for sleep is approaching. Melatonin supplements are widely available and can be effective for circadian rhythm disorders. A circadian rhythm disorder is when your body’s biological clock is out of sync with societal norms including with your obligations. Some examples of circadian rhythm disorders are delayed sleep-wake phase (night owl), jet lag, and shift work disorder.

When it gets dark at nighttime your body starts to produce melatonin. Melatonin starts your body clock and prepares you for sleep. Melatonin levels usually rise in the evening and remain high throughout the night. Levels drop in the morning when it is time to be awake.

What are the forms of melatonin?

Over-the-counter melatonin supplements are available in doses of 1-10 mg. Melatonin is sold as a dietary supplement and is not regulated by the FDA. So, it is possible for the content of the supplement to differ from what is listed on the product label. Before you take melatonin be sure the brand is reputable and discuss taking this and any supplement with your doctor. The American Academy of Sleep Medicine states that melatonin supplements appear to be safe. There is no evidence of serious risks related to their use, but the long-term effects are unknown.

Snacks and beverages marketed as “relaxation” or “chill out” products containing various doses of melatonin along with other ingredients also are available. These products are not regulated by the FDA and are not guaranteed to be effective.