Melatonin stopped working? Why, and what to do instead
Melatonin often seems to stop working because it was never strong for insomnia in the first place: in trials it helps people fall asleep only about 7 minutes faster on average. Other common reasons are the wrong timing, a dose that's too high, a product that doesn't contain what the label says, or a sleep problem that has changed into habit-driven insomnia, which melatonin can't fix.
Taking more rarely helps. What usually works better is timing a small dose correctly if your body clock runs late, or switching to the habit steps of CBT for insomnia if you lie awake from worry or habit. Below: what melatonin does, the reasons it stops working with a test for each, a timing table, how to stop taking it, how to sleep without it, and when to see a doctor.
What melatonin actually does
Melatonin is a hormone your brain releases in the evening when light fades. It doesn't knock you out. It tells your body clock "it's night now". That makes it good at moving the timing of sleep, and weak at forcing sleep when your clock already says night.
- For general insomnia: a review of 19 trials found melatonin cut time to fall asleep by about 7 minutes and added about 8 minutes of sleep on average (Ferracioli-Oda and colleagues, 2013). The American Academy of Sleep Medicine's 2017 guideline suggests not using it to treat chronic insomnia in adults, because the benefit is small.
- For a late body clock (you can't sleep until 1 or 2 a.m. but sleep fine after that), timed melatonin is recommended by the same academy's 2015 circadian guideline.
- For jet lag: a Cochrane review found it helped, with 0.5 mg working about as well as 5 mg (Herxheimer and Petrie, 2002).
In the US, melatonin is sold as a dietary supplement. It isn't approved by the FDA as a sleep medicine, and supplements aren't checked for dose before they're sold (National Center for Complementary and Integrative Health).
Why melatonin stopped working: the reasons, and a test for each
| Reason | Signs it's you | What to try |
|---|---|---|
| It helped a passing problem that's now a habit | It worked during a stressful spell or a trip; now you lie awake worrying about sleep | CBT-I steps (below); melatonin won't touch this |
| Wrong timing | You take it at bedtime, or at a different time each night | Same time daily; earlier if your clock runs late (table below) |
| Dose too high | 5 to 10 mg; groggy or headachy mornings, vivid dreams, waking in the night | Try 0.5 to 1 mg, taken earlier |
| The product | Effect changed when you switched brand or bottle; gummies | A product with a USP Verified mark |
| Bright light at night | Ceiling lights, a bright phone or TV in the last hour | Dim, warm light for 1 to 2 hours before bed |
| Caffeine, alcohol, nicotine | Coffee after lunch, wine at dinner, evening vaping | Caffeine by noon; alcohol 3+ hours before bed |
| Irregular schedule | Bed and wake times swing 2+ hours between workdays and weekends | One wake-up time, 7 days a week |
| A new cause | Night sweats, pain, reflux, snoring, restless legs, a new medicine, low mood | See your doctor; treat the cause |
| Expecting a sleeping pill | You hoped to feel knocked out, and don't | Judge it by your sleep diary over 2 weeks |
The label may not match the bottle
This one surprises people. A Canadian study tested 31 melatonin supplements and found their actual melatonin ranged from 83% less to 478% more than the label, and the dose varied between batches of the same product (Erland and Saxena, 2017). A 2023 US study of 25 melatonin gummy products found most held between 74% and 347% of the labelled amount, and one had none at all (Cohen and colleagues, JAMA). If your melatonin "stopped working" when you opened a new bottle, it may be the bottle. A USP Verified mark means an independent lab checks that the product holds what the label says.
Does your body get used to melatonin?
There's little evidence that melatonin builds tolerance the way some sleeping pills do. Trials of prolonged-release melatonin over several months found no loss of effect and no rebound insomnia or withdrawal when people stopped. What's more common is that the problem changed. Many people start melatonin during a hard patch; the patch ends, but weeks of lying awake have left a learned link between bed and being awake. That's insomnia driven by habit and worry, and melatonin was never going to fix it.
Should you take more melatonin?
Usually not. Higher doses don't make it work much better for insomnia, and they stay in your blood longer, which can mean morning grogginess, headaches and vivid dreams. For moving the body clock, small doses are often enough: in one lab study, 0.5 mg moved the clock about as much as 3 mg when timed in the afternoon (Burgess and colleagues, 2010). Doses sold in the US often start at 3 to 10 mg. If you take melatonin, ask your doctor or pharmacist whether a lower dose, taken earlier, makes sense for you.
When to take melatonin, by what you want it to do
| Goal | Timing used in studies and guidelines | Notes |
|---|---|---|
| Move a late body clock earlier | A small dose several hours before your current natural sleep time, the same time daily | Pair with morning light and a fixed wake-up time; works over weeks |
| Jet lag, flying east | Near the local target bedtime at your destination, for a few days | 0.5 mg and 5 mg worked similarly |
| Falling asleep at a normal bedtime | About 30 to 60 minutes before bed | Expect a small effect (minutes, not hours) |
| Staying asleep at 3 a.m. | Not recommended in the middle of the night without advice | Short-acting forms wear off; can leave you groggy in the morning |
If you can't fall asleep until 2 a.m. most nights, our guide to a late body clock has a full plan with clock times and light.
Can't fall asleep without melatonin?
If you've taken it every night for months, the first nights without it can feel harder. Some of that is expectation: the pill had become part of your bedtime signal, and taking it away raises worry. Some is the original problem showing itself again. Melatonin itself isn't known to cause physical dependence. To stop:
- Pick a calm fortnight, not the week of a big deadline or a trip.
- Step down: halve your dose for a week, then halve again, then stop. Many people stop at once without trouble; stepping down makes it feel easier.
- Keep the ritual, swap the pill. Same time, same wind-down, a warm drink or a few minutes of slow breathing instead.
- Fix your wake-up time for the whole fortnight, whatever the night was like.
- Use the 20-minute rule. If you're awake and tense in bed, get up, do something calm in dim light, and come back when sleepy.
- Expect 2 or 3 rougher nights, then judge it by your diary, not by one night.
If you take melatonin for a diagnosed condition, or with other sleep medicines, talk to your doctor before stopping.
How to fall asleep without melatonin
The approach with the most evidence for long-term trouble sleeping is CBT for insomnia, which the American Academy of Sleep Medicine (2021) strongly recommends and the American College of Physicians (2016) recommends before any medicine. Its main steps:
- A fixed wake-up time every day, which sets the clock and lets sleep pressure build.
- A sleep window that matches the hours you actually sleep, so sleep gets deeper and comes faster, then widens in 15-minute steps. See sleep restriction for insomnia.
- Stimulus control: bed only when sleepy, up after about 20 minutes awake. See stimulus control therapy.
- Worry and thought work, so a bad night stops feeling like an emergency. See sleep anxiety.
- A wind-down with dim light, a warm shower 1 to 2 hours before bed, and tomorrow's to-do list written down. See how to fall asleep faster at night.
The free 2-minute sleep quiz works out your minutes awake in bed and a starting sleep window from your own answers.
A 2-week plan if melatonin has stopped working
Week 1: find the reason
- Keep a sleep diary each morning: to bed, rough time asleep, wakings, out of bed, melatonin dose and time.
- Set one wake-up time for all 7 days.
- Check the bottle: dose, form, a USP Verified mark. If you take 5 mg or more, ask your pharmacist about a lower dose.
- Move your last caffeine to noon and dim the lights 2 hours before bed.
- Look at the diary on day 7: are you mostly awake at the start of the night with a late clock (timing), or lying awake on and off with worry (insomnia)?
Week 2: act on it
- Late clock: morning light within an hour of waking, wake-up time 15 to 30 minutes earlier every 2 to 3 days, and if you use melatonin, a small dose at a fixed time well before bed, after checking with your doctor or pharmacist.
- Insomnia: step down the melatonin, start the 20-minute rule, go to bed only when sleepy, and do 15 minutes of written worry at a table each evening.
Who should check with a doctor before taking melatonin
The National Center for Complementary and Integrative Health and the NHS list these: people who are pregnant or breastfeeding, people with epilepsy, autoimmune conditions, liver or kidney disease, and people taking blood thinners (such as warfarin), seizure medicines, diabetes medicines, blood pressure medicines, medicines that suppress the immune system, or other sedatives. Don't drive or use machinery if it makes you drowsy.
When to see a doctor
- Trouble sleeping 3 or more nights a week for 3 months, or it's affecting work, mood or driving.
- Loud snoring, gasping or pauses in breathing at night, or very sleepy days (sleep apnea).
- Restless, crawling legs in the evening, which can be linked to low iron.
- Hot flushes or night sweats, pain, reflux, or getting up to urinate several times a night.
- Low mood or anxiety most days.
Ask about CBT-I; it's offered by sleep clinics, psychologists and digital programs.
Frequently asked questions
Why does melatonin work sometimes and not other times?
Because it works on timing. On nights when your clock was running late, it can help; on nights when stress, caffeine or a late nap is the cause, it can't do much. Product doses can also vary between bottles.
Why do I wake up in the night after taking melatonin?
Standard melatonin is short-acting and wears off within a few hours. Higher doses can also bring vivid dreams. Waking itself usually has other causes; see how to stop waking up at night.
Can melatonin make insomnia worse?
Taken at the wrong time (for example in the morning) it can shift your clock the wrong way. High doses can leave you groggy, which can lead to naps and a later night.
Should I take a break from melatonin?
There's no strong evidence that breaks restore its effect, because tolerance isn't well shown. A break is a good way to find out whether it's still doing anything for you.
Is it safe to take melatonin every night?
Short-term use appears safe for most adults. Long-term safety is less studied, which is one more reason to use the lowest dose, for the shortest time, with your doctor's advice.
What's better than melatonin for insomnia?
For long-term insomnia, CBT-I is the first recommended treatment. For short-term problems, a doctor may suggest other options.
Start this week
Keep a 7-night sleep diary, set one wake-up time, and look at your bottle's dose and label. Then decide: timing, or habit. If you want your own numbers worked out, take the free sleep quiz. More guides in our sleep guides.
Sources: Ferracioli-Oda E et al., Meta-analysis: melatonin for the treatment of primary sleep disorders, PLoS One, 2013. Sateia MJ et al., Clinical practice guideline for the pharmacologic treatment of chronic insomnia in adults, American Academy of Sleep Medicine, Journal of Clinical Sleep Medicine, 2017. Auger RR et al., Clinical practice guideline for the treatment of intrinsic circadian rhythm sleep-wake disorders, Journal of Clinical Sleep Medicine, 2015. Herxheimer A, Petrie KJ, Melatonin for the prevention and treatment of jet lag, Cochrane Database of Systematic Reviews, 2002. Erland LAE, Saxena PK, Melatonin natural health products and supplements: presence of serotonin and significant variability of melatonin content, Journal of Clinical Sleep Medicine, 2017. Cohen PA et al., Quantity of melatonin and CBD in melatonin gummies sold in the US, JAMA, 2023. Burgess HJ et al., Human phase response curves to three days of daily melatonin: 0.5 mg versus 3.0 mg, Journal of Clinical Endocrinology and Metabolism, 2010. Lemoine P et al., Prolonged-release melatonin improves sleep quality and morning alertness in insomnia patients aged 55 years and older and has no withdrawal effects, Journal of Sleep Research, 2007. Edinger JD et al., Behavioral and psychological treatments for chronic insomnia disorder in adults, Journal of Clinical Sleep Medicine, 2021. Qaseem A et al., Management of chronic insomnia disorder in adults, Annals of Internal Medicine, 2016. National Center for Complementary and Integrative Health, Melatonin: what you need to know, nccih.nih.gov. NHS, Melatonin, nhs.uk.