Is 5 mg of melatonin too much?
It’s the top of the useful range, and more than most nights need. Jet lag trials found nothing more above 5 mg, and taken at 10:30pm a 5 mg tablet stays above your own night’s peak until somewhere between 2:50 and 5:15am. A 5 mg gummy may hold anywhere from 3.7 to 17 mg.
5 mg tablets and gummies sit on every US drugstore shelf, so it feels like the standard dose. It’s a sensible ceiling for a trip across many time zones. For an ordinary Tuesday night it’s about 17 times your own melatonin at its peak.
We’d keep 5 mg for jet lag and try 1 mg for everything else, taken 1 to 3 hours before bed. If 1 mg at the right hour does nothing after two weeks, step up, and stop at 5.
It’s like packing a week of clothes for one night away. Nothing goes wrong, but you’re still carrying the extra the next morning.
Where 5 mg comes from
The cap is from jet lag research. In a 2002 Cochrane review of 10 trials in travelers, crew and soldiers, daily doses from 0.5 to 5 mg worked about the same, except that people fell asleep faster and slept better on 5 mg than on 0.5. Doses above 5 mg were no more effective. A 2024 analysis of 26 sleep trials landed close by, with the effect on falling asleep growing up to about 4 mg a day.
For moving your clock earlier, the hour does more than the dose. In a 2010 Chicago lab study, 0.5 mg moved the body clock about as far as 3 mg, each at its best time.
What a 5 mg night looks like
| 5 mg tablet at 10:30pm | |
|---|---|
| Peak | About 17 times a normal night’s peak, at about 11:10pm |
| Back under your own night’s peak | 2:50 to 5:15am |
| If it’s a gummy, most likely real dose | 6 to 8.5 mg |
| If it’s a gummy, full range found in tests | 3.7 to 17 mg |
The timing comes from a tablet’s measured half-life of about 54 minutes, with a slower 1.5 hours as the late end. The gummy range comes from a 2023 lab test of 25 US gummy products, where most held 1.2 to 1.7 times the label and the full spread ran from 74 to 347 percent.
When to think twice
If you take blood pressure medicine, ask first. In a 2000 trial, 5 mg at 10:30pm raised systolic blood pressure by about 6.5 points in people whose pressure was controlled on nifedipine. Anyone on a daily prescription should start with the medicines answer, and the same goes for anyone pregnant, breastfeeding or under 18.
If you wake up groggy on 5 mg, the grogginess answer explains why and what to change. Put 5 mg into the tool below with your alarm time to see what’s left by morning. Don’t drive after a dose.
6 sources
- Herxheimer A, Petrie KJ, Melatonin for the prevention and treatment of jet lag, Cochrane Database of Systematic Reviews, 2002pubmed.ncbi.nlm.nih.gov
- Cruz-Sanabria F and others, Optimizing the time and dose of melatonin as a sleep-promoting drug: a systematic review of randomized controlled trials and dose-response meta-analysis, Journal of Pineal Research, 2024pubmed.ncbi.nlm.nih.gov
- Cohen PA and others, Quantity of melatonin and CBD in melatonin gummies sold in the US, JAMA, 2023pubmed.ncbi.nlm.nih.gov
- Burgess HJ, Revell VL, Molina TA, Eastman CI, Human phase response curves to three days of daily melatonin: 0.5 mg versus 3.0 mg, Journal of Clinical Endocrinology and Metabolism, 2010pubmed.ncbi.nlm.nih.gov
- Andersen LP and others, Pharmacokinetics of oral and intravenous melatonin in healthy volunteers, BMC Pharmacology and Toxicology, 2016pubmed.ncbi.nlm.nih.gov
- Lusardi P, Piazza E, Fogari R, Cardiovascular effects of melatonin in hypertensive patients well controlled by nifedipine, British Journal of Clinical Pharmacology, 2000pubmed.ncbi.nlm.nih.gov
