On this page
- Does more melatonin work better?
- How much does melatonin actually help you sleep?
- Melatonin dosage for jet lag
- Melatonin dosage for night owls (delayed sleep phase)
- When to take melatonin
- Is 10 mg of melatonin too much?
- The label may not match the bottle
- Side effects and safety
- Melatonin for children
- A careful way to try it
- Common questions
The short answer There’s no official adult dose. Studies have used anywhere from 0.3 to 10 mg, and more isn’t reliably better: for shifting your body clock, 0.5 mg worked about as well as 3 mg when timed well. The CDC’s travel guidance says 0.5 to 1 mg is often enough for jet lag and advises against more than 5 mg. Timing matters as much as the amount.
Melatonin is sold in the US as a dietary supplement, so nobody has set a standard dose the way they would for a drug. What we do have is a decent body of trials, a few official guidelines and one prescription product in Europe. Here’s what each says.
| Use | Evidence | What studies used | Timing in those studies |
|---|---|---|---|
| Jet lag | Moderate evidence | 0.5 to 1 mg is often enough (CDC); avoid more than 5 mg | Depends on flight direction (see below) |
| Delayed sleep phase (night owls who can’t fall asleep until very late) | Moderate evidence | 0.5 mg in a 2018 trial | 1 hour before the desired bedtime |
| Trouble falling asleep (insomnia) | Limited evidence | Roughly 0.5 to 10 mg across trials; effects modest | Usually 30 minutes to 2 hours before bed |
| Insomnia, adults 55 and older (Europe, prescription) | Limited evidence | 2 mg prolonged-release | 1 to 2 hours before bed, after eating |
| Shift work sleep | Weak evidence | Small, inconclusive trials | Varied |
None of this is a dosing instruction. It’s what researchers and regulators have used, so you have something concrete to discuss with a doctor or pharmacist.
Does more melatonin work better?
Not in a straight line, and the higher doses on store shelves are well beyond what many studies needed.
For moving your body clock, the clearest test compared 0.5 mg with 3 mg using the same lab protocol in 34 healthy adults. When each dose was taken at its best time, both produced similar-sized shifts. The smaller dose just needed to be taken a bit later in the day to do it.
For falling asleep, the picture is murkier. A 2024 dose-response meta-analysis of 26 randomized trials found the effect on time to fall asleep and total sleep rose with dose and peaked around 4 mg a day, and worked better when taken about 3 hours before bed rather than 30 minutes. Meanwhile, a review of studies in adults 65 and older, covering doses from 0.5 to 10 mg, found no clear dose-response relationship; doses of 1 to 6 mg appeared effective, but the minimum effective dose is still unknown.
A Cleveland Clinic sleep physician suggests using the lowest dose possible for the shortest time, starting at 1 mg and going up by 1 mg a week, never past 10 mg, only until it shortens the time it takes to fall asleep. That’s one clinician’s approach, and it’s a sensible frame: start low, change one thing at a time.
One regulated reference point exists. In the European Union, a 2 mg prolonged-release melatonin tablet is a prescription medicine for primary insomnia in adults 55 and older, taken 1 to 2 hours before bed for up to 13 weeks. In one of the trials behind it, 354 adults aged 55 to 80 took the tablet or a placebo 2 hours before bedtime for three weeks; 26% of the melatonin group improved on both sleep quality and morning alertness, versus 15% on placebo. That’s a slow-release form studied in older adults, so it doesn’t translate directly to a 2 mg gummy.
How much does melatonin actually help you sleep?
Less than the marketing suggests. A meta-analysis of 19 trials with 1,683 people found melatonin cut the time to fall asleep by about 7 minutes and added about 8 minutes of sleep compared with placebo. The authors called the effects modest, though they didn’t seem to fade with continued use.
That’s why the American Academy of Sleep Medicine’s 2017 guideline suggests clinicians not use melatonin for chronic insomnia in adults. It’s a weak recommendation, which under the guideline’s grading means uncertainty about the balance of benefit and harm, not proof that melatonin does nothing. NIH’s complementary health center sums it up: there’s not enough strong evidence on melatonin for chronic insomnia to recommend it.
Where melatonin does better is timing problems, which is what it does in the body anyway. It’s a darkness signal, not a sedative.
Melatonin dosage for jet lag
The CDC’s travel health guide says 0.5 to 1 mg is often sufficient to produce a circadian shift, and that high-dose melatonin over 5 mg isn’t recommended. It also notes that melatonin taken when your own levels are already high, roughly midnight to 5 am on your body clock, doesn’t work as well.
NIH’s summary of the trials found melatonin may beat placebo for jet lag after both eastward and westward flights, based on a handful of small studies. Flying east is usually harder, since you have to fall asleep earlier than your body wants. Timing depends on direction; one of the CDC’s sample plans has travelers take it 90 minutes before bed to support the natural evening rise. The CDC estimates people adapt by about 1 hour a day after eastward travel and 1.5 hours a day after westward travel.
Melatonin dosage for night owls (delayed sleep phase)
If you can’t fall asleep until 2 am no matter what, and sleep fine if you’re allowed to wake at 10, that’s a body-clock problem. In a 2018 randomized trial of 116 people with diagnosed delayed sleep-wake phase disorder, 0.5 mg taken 1 hour before their desired bedtime, combined with a fixed bedtime, moved sleep onset about 34 minutes earlier than placebo over four weeks. The AASM’s 2015 circadian guideline gave timed melatonin for this condition a weak recommendation in favor, according to NCCIH’s summary.
This is the use where getting the timing right with a sleep specialist pays off most, since the best time depends on when your own melatonin starts rising.
When to take melatonin
Two different jobs, two different timings.
- To help you feel sleepy at bedtime: Cleveland Clinic experts say it takes about 20 to 40 minutes to work and suggest taking it about 30 minutes before bed. The 2024 meta-analysis hints that earlier, around 3 hours before bed, may work better.
- To shift your body clock earlier: Take it several hours before your current natural sleep onset. In the dose comparison study, the biggest shifts came from 0.5 mg taken 2 to 4 hours before the body’s own melatonin rise, which for most people is in the evening.
Whatever the timing, melatonin is easy to overpower. Bright screens, a racing mind or a late coffee can cancel out a modest supplement. Our how to fall asleep fast guide covers the free methods that do more.
Is 10 mg of melatonin too much?
It’s more than most studies needed, and above the 5 mg ceiling the CDC suggests for jet lag. The trials don’t show 10 mg working better than lower doses for most people, and the most common complaint, next-day grogginess, is more likely when you take too much or take it too late. Cleveland Clinic lists drowsiness, sluggishness and delayed reaction times the next day as signs of that.
There’s also a labeling problem that makes “how many milligrams” fuzzier than it looks.
The label may not match the bottle
Because melatonin is a supplement, the FDA doesn’t approve it before it’s sold. A 2023 study in JAMA tested 25 melatonin gummy products and found the actual melatonin ranged from 74% to 347% of the labeled amount; only 3 were within 10% of the label, and one contained no detectable melatonin at all. An earlier study of 31 supplements found most didn’t match their labels, and 26% contained serotonin.
If you use it, a product with a third-party seal such as USP Verified is a reasonable step. The AASM notes this program is voluntary and covers few melatonin products, so a missing seal doesn’t prove a product is bad. It just means nobody independent has checked.
Side effects and safety
NCCIH says short-term use appears to be safe for most people, but long-term safety data are lacking. Commonly reported side effects include headache, dizziness, nausea, daytime drowsiness and vivid dreams, per Cleveland Clinic.
A few groups need more caution, according to NCCIH:
- People with epilepsy, and people taking blood thinners, should use it only under medical supervision.
- Older adults may find melatonin stays active longer and causes daytime drowsiness. The AASM recommends against melatonin for people with dementia.
- There’s little research on safety during pregnancy or breastfeeding.
You may also have seen 2025 headlines linking long-term melatonin use to heart failure. That came from a conference abstract using health records, which showed an association but not cause, and hadn’t been peer reviewed. A Cleveland Clinic cardiologist says there’s no clear evidence that melatonin causes heart failure, while noting the question is still open.
Melatonin for children
We won’t give children’s doses, and nobody reputable should without knowing the child. The AASM advises parents to talk to a pediatric health care professional first, treat melatonin like any other medicine, and keep it out of reach. Many children’s sleep problems respond better to changes in schedule and habits.
Storage matters. The CDC estimated about 11,000 emergency department visits from 2019 to 2022 for children 5 and under who got into melatonin unsupervised, many involving gummies.
When to see a doctor
Talk to your doctor or pharmacist first if you:
- take blood thinners, seizure medication or any prescription drug
- have epilepsy, dementia or another neurological condition
- are pregnant or breastfeeding, or want to give melatonin to a child
- have had trouble sleeping at least three nights a week for three months. That’s chronic insomnia, and cognitive behavioral therapy for insomnia is the treatment the AASM strongly recommends.
- snore loudly, stop breathing in your sleep or feel exhausted despite enough time in bed, which can point to sleep apnea
A careful way to try it
- Name the problem first. Jet lag or a body clock running late are the best-supported reasons. General insomnia is the weakest.
- Check your medications with a pharmacist. Especially blood thinners and seizure drugs.
- Start at the low end studies used. Many studies of body-clock problems used 0.5 to 1 mg, well below the 3 to 10 mg tablets common on shelves. Ask the pharmacist about lower-strength options.
- Pick the timing for the job. About 30 minutes to a few hours before bed for sleepiness; earlier in the evening for shifting your clock.
- Dim the lights and put the phone away. Light at night can block your own melatonin production, which works against the supplement.
- Keep a two-week log. Note bedtime, roughly how long it took to fall asleep and how you felt the next morning. If nothing changes, stop.
For how melatonin stacks up against magnesium and other options, see sleep supplements: what the evidence shows and magnesium for sleep. If the real issue is that bedtime keeps sliding later, what time you should go to bed is the better place to start. More guides are in Supplements.
Common questions
How much melatonin should an adult take?
There's no official adult dose. Studies have used about 0.5 to 10 mg, and for jet lag the CDC says 0.5 to 1 mg is often enough and advises against more than 5 mg. A doctor or pharmacist can help you choose, especially if you take other medicines.
Is 10 mg of melatonin too much?
It's more than most studies needed and above the 5 mg ceiling the CDC suggests for jet lag. Higher doses aren't shown to work better for most people and are more likely to leave you groggy the next day.
How long before bed should I take melatonin?
For sleepiness, Cleveland Clinic experts suggest about 30 minutes before bed, though a 2024 analysis found earlier dosing, around 3 hours before bed, worked better. To shift your body clock earlier, it's taken several hours before your natural sleep time.
Can I take melatonin every night?
Short-term use appears safe for most adults, but long-term safety hasn't been well studied. If you need a sleep aid most nights for months, talk to a doctor about chronic insomnia and CBT-I.
Written and checked by the Sleep Brief editors. We base every article on published research and guidance from medical bodies, and link the sources inline. How we research.
This article is for general education and isn't medical advice. If poor sleep lasts more than a few weeks, or you snore loudly, stop breathing in your sleep or feel sleepy while driving, talk to a doctor.
