The Health Benefits of Melatonin

A popular sleep aid, melatonin helps reset circadian rhythms and more

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Melatonin is a chemical that your brain makes when it gets dark outside. It's known as the sleep hormone because it tells you when to go to sleep and wake up.

You can buy melatonin supplements in most grocery stores or pharmacies. Studies have shown that these supplements are safe and have fewer side effects than many prescription sleeping pills.

This article will go over how melatonin is used, what the side effects and risks of using melatonin are, and when to see your provider about sleep issues that melatonin is not helping with.

When to Take Melatonin

Verywell / Joshua Seong

Health Benefits of Melatonin

Studies have shown that melatonin is safe and effective as a sleep aid. Medications are usually tested on just healthy adults, but researchers have tested melatonin on a lot of people, including children. 

Here are what studies have shown about using melatonin for sleep and other possible health benefits of the supplement.


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This video has been medically reviewed by Sanja Jelic, MD.

Using Melatonin for Sleep

Researchers have tested melatonin on people with insomnia. They have also looked at whether melatonin helps shift workers, military personnel, older adults, and kids.

Most studies have just looked at short-term melatonin use, ranging between a few days to just over three months.

Research has shown that melatonin may have these benefits:

  • Fall asleep faster: People who took melatonin fell asleep between 22 and 34 minutes sooner than people who took placebo pills.
  • Improve sleep efficiency: Sleep efficiency refers to the time you spend sleeping compared to the time you were in bed. Some studies have shown that taking melatonin might make your sleep efficiency better.
  • Help children fall asleep and stay asleep longer. Melatonin may help kids with sleep problems, such as those that are common in autism spectrum disorder and attention deficit hyperactivity disorder (ADHD).
  • Reset your sleep-wake cycle: When you feel like going to sleep and waking up is controlled by your circadian rhythm. Some studies have shown that melatonin may help regulate this cycle.

Is Melatonin Safe?

While research has shown that melatonin could be a safe way to improve sleep, experts say that better quality studies with larger groups of people and longer follow-up times are needed to provide more evidence that works and is safe to use.

Melatonin for Eye Health 

Several small studies have suggested that melatonin might help treat certain eye diseases that are caused by inflammation and aging.

One review looked at experimental studies and clinical trials done between January 1990 and September 2017. The findings showed that melatonin might be helpful for treating:

  • Uveitis: An eye disease that causes sudden redness, swelling, and pain in the eye.
  • Glaucoma: A group of eye disorders that are usually caused by pressure within the eye. If it's not treated, glaucoma can damage the optic nerve, which sends signals from your eye to your brain.
  • Age-related macular degeneration (ARMD): An eye disease that blurs central, straight-ahead vision in people 65 years of age and older. Most of the eye and melatonin research has been on ARMD. In one study, 100 patients with AMD were given 3 milligrams (mg) of melatonin a day for up to two years. The researchers found that melatonin helped protect the retina of the eye from more damage. While those findings were promising it was just one small study. More research would be needed to prove that melatonin is really helpful.

Researchers do not know why melatonin might help these eye conditions, but it might be because it reduces inflammation and oxidative stress from unstable molecules that can harm cells and tissues (free radicals).

Melatonin for Autism

Studies have shown that many autistic people do not make enough melatonin and often have sleep problems.

A 2014 review study found that melatonin helped autistic people fall asleep sooner. They also slept longer and more soundly. For some autistic people, improved sleep helped improve their daytime functioning and behavior.

However, more studies are needed to determine the best dosing and timing for using melatonin in autistic people.

Taking Melatonin for Jet Lag

Jet lag happens when you travel across time zones. For a few days after you've traveled, your body's internal clock will still be set to where you came from, not where you arrived. This can make you tired and you may have trouble focusing.

Research has shown that melatonin may help you get over jet lag symptoms. In fact, the American Academy of Sleep Medicine supports using melatonin to reduce jet lag and sleep better when you've been traveling across more than one time zone.

Melatonin for Tinnitus

Tinnitus is a chronic condition that causes you to hear ringing in your ears when there is no external sound. Tinnitus has no cure, but melatonin has been looked at as a possible treatment.

In a small study, 61 patients with tinnitus were given 3 mg of melatonin at bedtime. After a month, the researchers found the melatonin supplement seemed to reduce inner ear noise and improve sleep quality for people with tinnitus.

Possible Side Effects of Melatonin

There are severe side effects of taking melatonin, including drowsiness, headache, dizziness, nausea, and nightmares. Melatonin may also cause agitation and bedwetting in kids.

If you take too much melatonin, you might feel "hungover," but the feeling usually goes away quickly.

Melatonin might stay active in the body longer in older adults. As a result, they might have daytime drowsiness if they use the supplement.

There are no reports of fatal overdoses caused by melatonin.

The lack of long-term studies means that it's not known whether melatonin is safe to take for a long time (extended use).

Melatonin Interactions and Warnings

Even though melatonin is sold over the counter (OTC), you should talk to your healthcare provider before taking it. This is especially true if you already take medication or supplements, or you have a medical condition.

Melatonin might change how your body processes some medications—for example, increasing or decreasing how much of a medication is in your system. Mixing medications with melatonin can also change how much melatonin is in your system.

  • Blood thinners: If you take medication to prevent blood clots, taking melatonin may increase your risk of bleeding.
  • Anticonvulsants: If you take epilepsy drugs, melatonin may make the medications less effective at preventing seizures.
  • Sedatives and tranquilizers: Melatonin may increase the calming effect of sedating medications.
  • Blood pressure medications: If you have hypertension, melatonin may raise your blood pressure.
  • Diabetes medications: People with diabetes may have higher blood sugar levels while taking melatonin.
  • Immunosuppressants: People with autoimmune diseases take drugs that weaken the body's immune system response. People who have had an organ transplant take drugs to stop their bodies from rejecting their new organs. Melatonin may make these medicines less effective.
  • Contraceptives: Some birth control pills may increase melatonin levels, making you feel drowsier.
  • Luvox (fluvoxamine): People with obsessive-compulsive disorder (OCD) may take Luvox to prevent unwanted thoughts or repeated actions, like washing their hands. The drug can increase melatonin levels, which may make you feel more sleepy.

If you are pregnant or breastfeeding, you should not take melatonin because there is not enough evidence to prove that it's safe.

Melatonin Dosage and Preparations

Melatonin is sold as an over-the-counter (OTC) dietary supplement in most grocery stores and pharmacies. You can also get different types of melatonin products online.

The Food and Drug Administration (FDA) does not require the same evidence of safety and effectiveness for supplements, including melatonin, as prescription and OTC medications.

Melatonin comes in several forms, including tablets, lozenges, and gummies.

There are no official dosing guidelines for melatonin. It typically comes in doses that range from 1 mg to 10 mg.

It's best to start with the lowest dose of melatonin and slowly increase the amount you take until you find what works for you.

In research studies, 3 mg of melatonin is a commonly used dose by people who use it for sleep benefits.

When to Take Melatonin

Melatonin plays a critical role in regulating your sleep-wake cycle, which means you need to take it at the right time of day.

Your brain naturally makes melatonin from sundown to sunrise. When you take a melatonin supplement, it takes about 30 minutes to reach peak levels in your blood.

Most people take melatonin about an hour before going to bed. However, there are certain conditions when it helps to take it at other times:

  • For trouble falling asleep: Take melatonin 30 minutes before bedtime. 
  • For night owls: People with delayed sleep phase syndrome may want to take melatonin several hours before they want to go to bed. For example, if you usually fall asleep at 2 a.m., but you want to go to bed at 11 p.m., try taking melatonin around 9 p.m.
  • For early birds: If you have symptoms of advanced sleep phase syndrome (where you fall asleep very early and wake up early) you can treat the condition with bright light timed to delay sleep onset. You may want to ask your provider if you could also take melatonin, and when the best time to take it would be.

What to Look For When Buying Melatonin 

The FDA does not oversee how companies make supplements. They also don't test their quality. If you buy a melatonin supplement, it may not be what it says that it is on the label.

A 2017 study analyzed 31 melatonin supplements. The levels of melatonin ranged from 83% lower to 478% higher than what the product labels stated. In some cases, even different bottles of the same product varied a lot.

When you're choosing a melatonin supplement, look for a brand that has been certified by Consumer Lab or the United States Pharmacopeia (USP).


Melatonin might help you fall asleep sooner and stay asleep longer. Researchers have tested the supplements in a wide range of people, including children. Studies have shown that a melatonin supplement might help reset your natural sleep-wake cycle.

Compared to prescription medications used to treat sleep disorders, melatonin may have fewer risks and side effects. It's also a supplement that you can buy at the pharmacy without a prescription.

However, be careful when choosing a melatonin supplement. Like other dietary supplements, they are not regulated by the FDA. You should also ask your provider before you start taking melatonin especially if you have a health condition or take medications.

A Word From Verywell

Not sleeping enough can make it hard to function at work or school. It can even affect your mental and physical health, increasing your risk of depression, obesity, and heart disease.

Melatonin is safe and effective as a short-term way to help with your sleep. However, if your sleep troubles are not getting better or are getting worse, it's important to talk to your provider. Poor sleep can have many causes, and you might need treatment beyond what melatonin can help with.

Frequently Asked Questions

  • Is it OK to take melatonin every night?

    Most of the research has only looked at short-term usage which ranges from a few days to 13 weeks. There isn't enough evidence to know whether long-term use of melatonin is safe.

  • How much melatonin is too much?

    There has not been a lot of research on whether it's possible to overdose on melatonin, even when it's used in very high dosages. That said, some people might be more sensitive to it.

    For example, older people naturally have lower melatonin levels and should ask their healthcare providers before taking melatonin. They might be advised to stick to relatively low doses.

  • How long does melatonin stay in the body?

    Melatonin has a half-life of 20 to 40 minutes. Studies have shown that the effects of melatonin tend to peak after about an hour.

  • Will drinking caffeine interfere with melatonin?

    Caffeine affects naturally occurring melatonin. You may want to stick to drinking non-caffeinated beverages when you're taking melatonin to help with sleep.

  • Can you get addicted to melatonin?

    Melatonin is a hormone that your body makes naturally. It isn't something that you can get addicted to or dependent on, and it won't cause withdrawal.

  • Which foods have melatonin?

    Research has shown that some foods like eggs and fish have some melatonin in them. If you don't eat animal products, some kinds of nuts and mushrooms also have a good amount of melatonin in them.

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Brandon Peters, MD
Brandon Peters, MD, is a board-certified neurologist and sleep medicine specialist.