The short answer
For most adults, a low dose is the right place to start. Cleveland Clinic sleep experts suggest beginning at 1 mg, using the lowest dose that works and raising it slowly only if needed. Large doses are more likely to leave you groggy the next day, and many store bottles go well past the amounts where research saw benefits rise.
| Typical range | Over-the-counter products run from 1 mg to 10 mg and higher. |
|---|---|
| Timing | About 30 minutes before bed, since it takes roughly 20 to 40 minutes to work. |
| Too much | Daytime drowsiness, sluggishness, headache, dizziness or nausea. |
Melatonin shelves are full of 5 mg and 10 mg bottles, which can make 2 mg look small. It isn't. Melatonin is a hormone your brain already makes in response to darkness, and a supplement is meant to nudge the timing of sleep, not knock you out. This guide covers what the research says about dose, how to time it, and who should check with a doctor first.
What does melatonin actually do?
Your brain releases melatonin as light fades, and it helps set your body's internal clock. Light at night suppresses it. That is why the National Center for Complementary and Integrative Health (NCCIH) describes melatonin as a regulator of sleep timing rather than a sedative, and why the strongest evidence is for problems of timing, such as jet lag and a delayed sleep schedule.
For long-term insomnia, guidelines from the American Academy of Sleep Medicine and the American College of Physicians found too little strong evidence to recommend melatonin. The American College of Physicians recommends cognitive behavioral therapy for insomnia (CBT-I) as the first step instead.
How much melatonin should I take?
Cleveland Clinic sleep specialists recommend starting at 1 mg and using "the lowest dose possible for the shortest amount of time." Their suggested approach is to raise the dose slowly, by 1 mg a week, only if you still take a long time to fall asleep.
A 2024 review in the Journal of Pineal Research looked at 26 randomized trials. The review noted that 2 mg about 30 minutes before bed is the most common clinical regimen, but its data suggested larger doses (up to about 4 mg) taken around 3 hours before bed worked better. Cleveland Clinic still advises starting at 1 mg and using the lowest dose that works. Either way, the 5 mg and 10 mg bottles on the shelf go past the range where the review saw benefits rise, and timing is a lever many people overlook.
| Dose | Where it fits | What to know |
|---|---|---|
| 1 mg | The starting dose Cleveland Clinic experts suggest | A good first step if you are sensitive to sleep aids |
| 2 mg | The most common clinical regimen, about 30 minutes before bed | A common, moderate starting amount |
| 3 to 4 mg | Upper end of the benefit seen in a 2024 review | Worth discussing with a doctor before moving up |
| 5 to 10 mg | Common on store shelves | Not shown to be better for sleep; more likely to cause daytime drowsiness |
General information for adults. Children should only take melatonin on a pediatrician's advice.
Why not start with a bigger dose?
Cleveland Clinic notes that taking too much, or taking it too late in the evening, can lead to daytime drowsiness, sluggishness and slower reaction times, and can gradually make some sleep problems worse. NCCIH adds that long-term safety data are lacking, especially at doses above what the body normally makes.
Label accuracy is another reason to start low. NCCIH reports that a 2017 study of 31 supplements found most did not match their labeled melatonin amount, and a 2023 study of 25 gummies found 22 were mislabeled, ranging from 74% to 347% of the stated amount. A clearly stated, moderate amount from a brand you trust leaves less room for surprises.
Check the melatonin amount per serving on the supplement facts panel, not just the front of the bottle.
When should I take melatonin?
- Start about 30 minutes before bed. Cleveland Clinic says melatonin takes roughly 20 to 40 minutes to work. The 2024 review suggests taking it earlier in the evening may help some people, so ask your doctor about timing if bedtime dosing is not working.
- Keep the room dark. Bright light and screens work against melatonin.
- Allow time for a full night. Mayo Clinic advises not driving or operating machinery within 5 hours of taking it.
- Skip alcohol and other sleep aids on the same night.
Talk to your doctor first if you
- Take blood thinners, seizure medication, blood pressure or diabetes medication, immunosuppressants, antidepressants or any prescription medicine.
- Have epilepsy, an autoimmune condition, or a liver or thyroid condition.
- Are allergic to ragweed or daisy-family plants. HealthBuy Sleep Aid says to avoid it in that case.
- Are pregnant or breastfeeding. Research in these groups is limited.
- Are an older adult. NCCIH notes melatonin may stay active longer and cause daytime drowsiness.
- Have trouble sleeping most nights for weeks, snore loudly or feel very sleepy during the day. Those deserve a medical evaluation.
Where HealthBuy fits
HealthBuy Sleep Aid lists 2 mg melatonin per serving, with 200 mg L-theanine, 150 mg magnesium as glycinate, glycine, GABA, KSM-66 ashwagandha and calming botanicals. It is designed for adults who want occasional sleep support as part of a regular wind-down routine.*
HealthBuy Sleep Aid
2 mg melatonin per serving with L-theanine and magnesium glycinate. For adults only; do not combine with alcohol, sleep medication or other sedatives.
See the full formulaKeep reading
- Caffeine-Free Focus: What Citicoline, Bacopa and Lion's Mane Do
- How to Choose a Quality Supplement: A Practical Label Checklist
- Shop sleep support
Frequently asked questions
How much melatonin should I take?
Start low. Cleveland Clinic experts suggest 1 mg as a starting dose and the lowest dose that works. 2 mg is the amount most used in clinical practice.
Is 10 mg of melatonin too much?
It is more than most adults need. A 2024 review found sleep benefits peaked at about 4 mg, and higher doses are more likely to cause next-day drowsiness. Ask your doctor before taking large doses.
How long before bed should I take melatonin?
About 30 minutes before bed for most people. Melatonin takes roughly 20 to 40 minutes to work.
Can I take melatonin every night?
Short-term use appears safe for most adults, but long-term safety is not well studied. If you need a sleep aid most nights, talk to your doctor about the cause.
Why does melatonin make me groggy in the morning?
The dose may be too high or taken too late. Try a lower dose or taking it earlier, and allow time for a full night's sleep.
Sources
- Melatonin: What You Need To Know, National Center for Complementary and Integrative Health
- How Much Melatonin Should I Take?, Cleveland Clinic
- Melatonin, Mayo Clinic
- Optimizing the Time and Dose of Melatonin as a Sleep-Promoting Drug: A Systematic Review and Dose-Response Meta-Analysis, Journal of Pineal Research, 2024
For general information only; not medical advice. Talk to your doctor or pharmacist before starting a supplement, especially if you take medication, are pregnant or nursing, or manage a health condition. *These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease.
