Verbatim response from Perplexity
Usually, melatonin is not considered habit-forming, and you’re unlikely to become physically dependent on it. Mayo Clinic says that unlike many sleep medicines, melatonin is unlikely to cause dependence or reduced effectiveness over time, and Johns Hopkins notes that it is generally safe for most people to take nightly for 1 to 2 months if it helps[9][8].
A few important caveats:
- Long-term nightly use is not as well studied as short-term use, and several clinical sources recommend using the lowest effective dose for the shortest time needed[9][7][8].
- A 2025 observational study reported an association between long-term melatonin use in adults with insomnia and higher rates of heart failure and death, but the authors and cardiology groups emphasized that this does not prove cause and effect[1][2][6].
- A 2023 review found that low-to-moderate doses, roughly 5–6 mg daily or less, generally appear safe and that common side effects are usually mild, such as headache and sleepiness[4][5].
What this means practically:
- If you’re using melatonin every night for a short period, dependence is unlikely[9][8].
- If you feel you need it for weeks to months, it’s worth talking with a clinician to look for the cause of the insomnia and to review dose, timing, and any medication interactions[8][7].
- If you have pregnancy/breastfeeding, autoimmune disease, seizure disorder, depression, diabetes, or high blood pressure, check with a healthcare professional first because melatonin may not be appropriate or may interact with some conditions/medications[8].
If you want, I can also tell you the best dose and timing for melatonin to minimize grogginess and avoid taking too much.