“Yes, you can overdose on melatonin, in the sense of taking more than your body handles comfortably, but for adults a life-threatening overdose on melatonin alone is rare. Too much usually means heavy sleepiness, headache, nausea or dizziness that can last for hours. The bigger dangers are mixing it with alcohol or sedating medicines, driving while drowsy, and children eating gummies.”
Maybe you took a second dose when the first one didn't seem to work. Maybe you found an open bottle of gummies and a toddler with a sticky face. Either way, you want to know fast whether you can overdose on melatonin and how worried to be.
If someone is hard to wake or isn't breathing normally, call 911 now. For anything else, US Poison Control is free, confidential and open 24 hours a day at 1-800-222-1222. Below is the calm version of everything else: what too much melatonin does, the 7 warning signs, what 20mg and higher doses mean, and how to keep children safe.
Can you overdose on melatonin? What "overdose" means here
In everyday speech, an overdose means taking more than your body can comfortably handle. By that definition, yes, it's possible. In the scarier sense, a poisoning that threatens your life, it's very uncommon in adults.
Poison Control's melatonin guide says someone who takes too much may have sleepiness, headache, nausea and perhaps agitation. It adds that there's no antidote, and that significant toxicity isn't expected even after relatively large doses. The drowsiness can last for several hours.
Research on higher doses points the same way. A 2022 review of trials that gave adults 10 mg or more found no detectable rise in serious adverse events in the four most rigorous studies. It did find more drowsiness, headache and dizziness, and the authors stressed that the evidence was limited.
So for a healthy adult, too much melatonin usually means hours of heavy sleepiness, perhaps with a headache or nausea, rather than a medical emergency. The exceptions are the situations further down: alcohol or sedating medicines on board, a drive to make, a large amount taken on purpose, or a child who got into the bottle.
Melatonin overdose symptoms: 7 warning signs
These are the signs that you, or someone you're watching, took more melatonin than their body wanted. The first five are usually uncomfortable rather than dangerous. The sixth is about children, and the seventh means calling 911.
1. Sleepiness that won't lift
Drowsiness is the effect everyone expects, and Poison Control notes it may last for several hours. A big evening dose can spill into the next morning, so you feel slow, heavy and hard to get going. Don't drive, cycle or use machinery until it has fully cleared. If foggy mornings after melatonin are a regular thing, our guide to the melatonin hangover covers why it happens.
2. A headache
Headache shows up in Poison Control's overdose advice, among the mild side effects that NCCIH reports from short-term studies, and in the higher-dose review. Rest, drink some water and skip alcohol.
3. Dizziness or feeling unsteady
NCCIH lists dizziness among melatonin's mild side effects, and the higher-dose review found more of it at 10 mg and up. If you feel dizzy, sit or lie down until it passes, and take the stairs slowly or with help.
4. Nausea or an upset stomach
Nausea is on both Poison Control's and NCCIH's lists. Sip water, keep food light and let it pass. If vomiting keeps up, or you can't keep fluids down, call Poison Control for advice.
5. Agitation or restlessness
It sounds backward for a sleep supplement, but Poison Control lists agitation as a possible effect of too much melatonin. If someone seems unusually agitated, keep things calm and quiet, and call Poison Control if it doesn't settle.
6. In a child: unusual sleepiness, bedwetting or agitation
NCCIH lists drowsiness, increased bedwetting or urination in the evening, headache, dizziness and agitation among the side effects reported in children. If a child may have eaten melatonin, call Poison Control even if they seem fine, so you know exactly what to watch for and for how long.
7. Hard to wake, or breathing that isn't normal
This is the one that can't wait. Poison Control says to call 911 or go to the nearest emergency department if the person's breathing isn't normal or they won't fully wake up. The same goes for a collapse, a seizure or any other emergency.
Is 20mg of melatonin too much?
Yes, for almost everyone. Twenty milligrams is twice the 10 mg threshold that the 2022 review used to define "high-dose" melatonin, and that review linked high doses to more drowsiness, headache and dizziness. NCCIH adds that for doses higher than what the body normally makes, there isn't enough information yet to have a clear picture of overall safety.
That doesn't make 20mg likely to poison a healthy adult. Poison Control says significant toxicity isn't expected even after relatively large doses. But "not toxic" isn't the same as "a good idea." Twenty milligrams means a bigger chance of drowsiness, headache and dizziness, which is the trade-off the higher-dose review points to.
If you've crept up to 20mg because a smaller dose stopped helping, take that as information rather than a reason to keep climbing. It may mean melatonin isn't matched to the kind of sleep problem you have. Our guide to whether 10mg of melatonin is too much explains how doses compare and how to step down.
Why there's no clear line for "too much"
Part of the problem is that "too much" has no fixed definition for a supplement. In the US, melatonin is sold as a dietary supplement, which NCCIH notes is regulated less strictly than a prescription or over-the-counter drug. Poison Control goes further: what counts as a melatonin overdose isn't well understood, and no standard dosage has been established.
The label adds another layer. NCCIH describes a 2017 test of 31 melatonin supplements in which the amount in most products didn't match the label, and 26% contained serotonin, a hormone that can be harmful even at fairly low levels. So the milligrams you think you took may not be the milligrams you swallowed.
What about 30mg, 50mg or more?
The bigger the amount, the longer and heavier the sleepiness is likely to be, and the more it matters what else is in the person's system. If someone took 30mg, 50mg or more, especially on purpose or alongside alcohol or other medicines, call Poison Control at 1-800-222-1222 for advice, and call 911 for any of the emergency signs above.
If you're thinking about taking a large amount to hurt yourself, please reach out now. In the US, you can call or text 988 at any time, day or night, and talk to someone who will listen.
Can melatonin kill you? The calm, sourced answer
The most detailed US numbers come from a CDC report on 260,435 melatonin ingestions by children and teens that were reported to poison control centers from 2012 to 2021. Most children (84.4%) had no symptoms. Five needed mechanical ventilation, and two died; both were under 2 years old and at home.
The report is careful about those two deaths. Poison center data don't include medical records or medical examiner reports, so the authors couldn't confirm whether either death was caused by melatonin alone or by other health problems. That uncertainty is part of the honest answer.
For a healthy adult, a deadly overdose on melatonin alone would be highly unusual; Poison Control says significant toxicity isn't expected even after relatively large doses. That's real reassurance, with clear limits. Alcohol, other sedating medicines, driving and a large amount taken on purpose all change the picture.
The bigger risks: alcohol, sedating medicines and driving
Much of the real danger in an overdose on melatonin comes from what's taken with it, and from what you do next.
Alcohol
The UK's NHS advises against drinking any alcohol while taking melatonin. It warns that the two together can make you sleep so deeply that you don't breathe properly and have trouble waking up. A nightcap on top of an extra dose is the combination to avoid.
Sedating medicines and supplements
Melatonin can interact with medicines and other supplements, so Poison Control and NCCIH both advise checking with your doctor before taking it alongside anything else.
Be especially careful with anything else that makes you drowsy: another sleep aid, a sedating allergy medicine, a prescription painkiller or a sleepy-making herbal product. Talk to your doctor or pharmacist before combining sleep aids, including supplements.
Driving and other risky tasks
The NHS says not to drive, ride a bike or operate machinery if melatonin makes you sleepy, gives you blurred vision, or makes you dizzy, clumsy or unable to concentrate. After a big dose, assume you're not safe to drive until the drowsiness has fully cleared, which can take several hours. Get a ride instead.
People who should be extra careful
- People with seizure disorders: Poison Control says they shouldn't take melatonin, because there are some reports of seizures in people who took it.
- Anyone on blood thinners or with epilepsy: NCCIH says they need medical supervision while using melatonin.
- Older adults: NCCIH notes that melatonin may stay active longer in older people and cause daytime drowsiness.
- Pregnant or breastfeeding: NCCIH notes a lack of research on safety. Ask your doctor before taking any.
Melatonin and children: gummies that look like candy
In the CDC report, melatonin ingestions by children and teens rose 530%, from 8,337 in 2012 to 52,563 in 2021. Almost all of them (94.3%) were unintentional, and 99% happened at home.
Most of those children had no symptoms. But over the decade, 4,097 were hospitalized and 287 needed intensive care. Most hospitalized patients were teenagers who had taken melatonin on purpose, while the biggest increase in hospitalizations was among children 5 and under who swallowed it by accident.
Gummies are a big part of the story. NCCIH cites a 2024 CDC estimate of about 11,000 emergency department visits from 2019 to 2022 for unsupervised melatonin ingestion by children 5 and under, and many of those incidents involved flavored products such as gummies.
- Store it up and away, out of children's reach and sight, in a locked cabinet if you can.
- Choose child-resistant packaging. The CDC report says child-resistant packaging for melatonin should be considered.
- Close the bottle every time, and don't leave gummies in a bag, a car or on a nightstand.
- Never call it candy, even to get a child to take it.
- Ask first. NCCIH advises parents to speak with a health care provider before giving a child melatonin.
For teenagers, NCCIH notes that over-the-counter melatonin may put children and teens at risk of accidental or intentional overdose. Keep an eye on how much is in the house. If your teen is struggling, talk with them and their doctor, and remember that 988 is there for them too.
At a glance: what to do if someone took too much
If an adult took an extra dose: stay home and stay put · no alcohol, no other sleep aids · no driving until the drowsiness is fully gone.
If someone may have taken an overdose on melatonin: call Poison Control at 1-800-222-1222 · free, confidential, 24 hours a day · have the bottle in your hand.
If a child got into melatonin: call Poison Control right away, even if they seem fine · keep the bottle · count what might be missing.
Call 911 if: breathing isn't normal · they won't fully wake up · they collapse or have a seizure · there's any other emergency.
Poison Control's melatonin guide also covers watching someone at home: a reliable adult should stay with the person until they're fully rested and awake, and wake them every half hour while they nap. If they won't fully wake up or their breathing isn't normal, call 911 or go to the nearest emergency department.
Have these ready when you call: the person's age and weight, the product and its strength, roughly how much they took and when, and anything else taken with it, including alcohol and other medicines.
If your dose keeps creeping up: a melatonin-free option
If you're reading this because your nightly dose has crept from 3mg to 10mg to 20mg, the dose may not be the real issue. More melatonin won't remove stress, pain or a sleep disorder, and it can make a groggy morning more likely. If you've slept badly most nights for three months or more, or you snore loudly or gasp at night, see a doctor.
If you'd like a natural sleep aid that doesn't involve picking a melatonin dose at all, a melatonin-free sleep spray takes that question off the table. Adapt X.1 has no melatonin and no sedatives: just an extract of natural grasses (Zea mays) as its single plant active, plus purified water and natural mint. You take it as directed, 6 to 10 sprays (0.75 ml) in your mouth about 30 minutes before sleep, then swallow, and it's non-habit forming.
In a double-blind, placebo-controlled clinical trial, people taking it fell asleep 33% faster than with placebo and had 30% fewer wake-ups in the night. Individual results vary. Most people feel their rhythm settle between weeks two and four of nightly use, and a 60-night money-back guarantee gives you time to see whether a single bottle suits you.
If you're pregnant or breastfeeding, have a medical condition or take other medicines, check with your doctor or pharmacist before you start, and don't stack it with other sleep aids without asking.
Questions people ask
Can you overdose on melatonin gummies?
Yes. Many accidental ingestions by young children involve flavored products such as gummies, according to the CDC estimate NCCIH cites. For adults, the catch is the label. NCCIH describes a 2023 test in which 22 of 25 gummy products were mislabeled: one had no detectable melatonin, and the rest held 74% to 347% of the stated amount.
What happens if you take two doses by accident?
For most healthy adults, an accidental double dose usually means extra drowsiness, maybe a headache, and a slow start the next morning. Don't drive until you're fully alert, skip alcohol and don't take anything else to sleep. Call Poison Control if you feel unwell or you're not sure what you took.
How long does too much melatonin last?
Long enough to plan around. Poison Control notes that the drowsiness can last for several hours, so a big dose late at night can carry into your morning. Give yourself time before you drive, and don't take more the next night to "catch up."
Is melatonin safe for kids?
Only with a doctor's guidance. NCCIH says normal doses appear safe for most children in the short term, but there aren't many studies, little is known about long-term effects, and because melatonin is a hormone, it might affect hormonal development, including puberty. Talk to your child's health care provider first, and lock it away either way.
The bottom line
Can you overdose on melatonin? Yes, in the sense of taking more than your body handles well, but for adults a dangerous overdose on melatonin alone is rare. Expect hours of sleepiness, and maybe a headache, dizziness or nausea. The real risks are alcohol, sedating medicines, driving and children finding gummies.
Keep melatonin locked away, keep Poison Control's number handy (1-800-222-1222), and call 911 if someone's breathing isn't normal or they won't wake up. If your dose keeps climbing, talk to your doctor, and consider a melatonin-free option such as Adapt X.1. If you're ready to step away from melatonin, our guide to a melatonin alternative covers the habits that help, and if nightly use is the worry, read is melatonin addictive.