Can You Overdose on Melatonin?

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Medical Disclaimer: The following content should not be used as medical advice or as a recommendation for any specific supplement or medication. It is important to consult your healthcare provider prior to starting a new medication or altering your current dosage.

Melatonin is a sleep-promoting hormone our bodies naturally create. Melatonin supplements can also be taken as an oral supplement to promote sleep. Although melatonin supplements are usually synthetic, many people view them as natural sleep aids since they mimic the hormone that is created by the body.

Research shows melatonin supplements can be useful for treating short-term sleep issues, like jet lag. If you are interested in taking melatonin to help you sleep, you might wonder if doing so comes with a risk of side effects or even the potential for overdose. We’ll explain if you can overdose on melatonin, how much to take if you decide to try it, and when to talk with your doctor.

Can You Overdose on Melatonin?

Although melatonin overdose is very rare, records of a few cases suggest that overdosing on melatonin supplements is possible. Instances of overdose appear to be more common in infants and in people who have taken unusually large doses of melatonin or combined it with other drugs. There are no records of melatonin overdose causing death in adults.

In three recent but separate cases, infants were found unresponsive after they were given melatonin. In the first case, experts determined that one infant died from melatonin overdose together with overheating. The cause of death in the other two cases was considered undetermined, though melatonin might have played a role. In all cases, melatonin was likely given to the infants to promote sleep.

In 2001, hospital staff in Hong Kong reported admitting three people who had attempted to commit suicide by taking large amounts of melatonin. Two more presumed suicide attempts involving melatonin supplements were reported in 2012 and 2019. All of these people appear to have survived.

In an older case report, a 66-year-old man became disoriented and sluggish after taking 24 milligrams of melatonin the night prior to a surgery. He later recovered and continued to take 6 milligrams of melatonin each night without issue. Larger amounts of melatonin taken by adults may cause overdose-like effects, especially if taken with other medications that might cause an interaction.

How Much Melatonin Should You Be Taking?

To take melatonin safely, you want to make sure you are taking an appropriate dose of melatonin. Consult with your physician to determine the dose that is right for you or your child.

Adults

More research needs to be done on the optimal melatonin dosage and timing, but most adults who take melatonin for sleep ingest between 0.5 and 5 milligrams about an hour before going to sleep. It is best to err on the side of caution, beginning with a low dose and slowly increasing the amount you take each night until you reach the optimal dose, as directed by your physician.

There is ongoing research into the use of melatonin supplements as part of cancer treatment. When used as an anticancer treatment, melatonin may be taken at higher doses. However, people with cancer should only take higher doses of melatonin under the supervision of their doctor.

Children

Research suggests melatonin supplements can promote sleep in children with sleep problems, including those who also have attention deficit hyperactivity disorder (ADHD), autism, eczema, or insomnia. However, there are no set recommended dosage amounts. Talk with your child's pediatrician before giving your child melatonin.

Shoppers should be aware that the Food and Drug Administration (FDA) does not regulate melatonin supplements. This means there are no official guidelines on dosage, and it also means supplements may contain more or less melatonin than what is stated on the package.

Symptoms of Melatonin Overdose

In instances of overdose, a person taking a large amount of melatonin might feel disoriented or experience lower blood pressure.

Generally, people using melatonin on a short-term basis only experience mild side effects, such as headaches, nausea, and dizziness. More rarely, taking a higher dose of melatonin may cause a rash, nightmares, stomach problems, or trouble sleeping. Long-term use of melatonin supplements has not yet been fully studied, though research so far indicates that melatonin does not appear to be habit-forming. Studies on animals suggest that melatonin is not fatal even at very high doses.

Extra care should be taken if you take melatonin along with other medications, as one may influence the other. For example, taking melatonin together with blood thinners may raise the risk of bleeding, and taking melatonin with other sleep aids may cause excessive sleepiness.

What to Do If You Think You Have Overdosed on Melatonin

If you experience negative effects after taking melatonin supplements and you are in the U.S., consult the national poison control helpline online or by phone at 1-800-222-1222. If your symptoms feel severe, call 911 or have someone take you to the nearest emergency room. Be sure to inform your care provider if you have been taking any other medications or substances that might interact with melatonin.

When to Talk to Your Doctor

Consider talking to your doctor about your sleep troubles before trying melatonin supplements. There may be other ways to improve your sleep without needing to take sleep aids, such as practicing good sleep hygiene or treating an underlying sleep disorder. Your doctor can help you identify potential underlying causes for your sleep problems and work with you to determine if melatonin is a good choice for your unique situation.

References

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