Why Can't You Buy Melatonin in Japan? (And What to Use Instead)
Melatonin is not sold over the counter in Japan because the health ministry classifies it as a medicine, not a food supplement. It is not a banned substance, and you can bring up to one month's supply for your own use. The closest medicine available here is ramelteon, which a doctor can prescribe and which pharmacies have also sold without a prescription since July 2026. How prescribing works in general is in our guide to psychiatric medication in Japan.
Why is melatonin not sold in Japan?
Because Japan classifies melatonin as an ingredient used only in medicines. A product that contains it counts as a medicine here, even if it is sold as a supplement abroad, so it cannot be sold in Japan as a food supplement. The health ministry's expert working group reviewed the classification in 2023 and kept it (the page is in Japanese). In the United States melatonin is regulated as a dietary supplement, which is why it is sold freely there.
The one melatonin medicine approved in Japan, Melatobel (メラトベル, Meratoberu), is a prescription medicine for children. It is approved for difficulty falling asleep in children with neurodevelopmental conditions, and its approval does not cover adults.
Is melatonin illegal in Japan, and can you bring your own?
It is not illegal to have, and you can bring up to one month's supply for your own use. Because melatonin counts as a medicine, the health ministry's personal import rules for medicines apply:
- Quantity: up to one month's supply comes in without paperwork, because Japan treats melatonin as a prescription medicine. Above that, you need an import certificate, and the application requires a prescription or a note from a doctor.
- Personal use only: what you bring in cannot be sold or given to anyone else, and you cannot import it for another person.
Our guide to bringing medication into Japan explains how the import certificate works.
What can you use instead?
Ramelteon (Rozerem), a medicine that acts on the same melatonin receptors. There are two ways to get it:
- By prescription: a doctor can prescribe it, including from a first online visit (the online rules), and insurance covers it like any other prescription
- From a pharmacy: since July 2026 ramelteon has been sold without a prescription as Rozerem S, after an explanation from a pharmacist. The label limits it to temporary trouble falling asleep in people aged 15 and over, and says not to take it for more than two weeks without asking a doctor or pharmacist
Ramelteon is approved for difficulty falling asleep, and it is not habit-forming. It is not designed for waking in the middle of the night, and it is not a strong sedative. If your sleep problem is broader than that, our guide to sleeping pills in Japan covers the other options.
Frequently asked questions
This article is general information, not medical advice for your individual situation. If you're unwell, please see a doctor.
Medically reviewed by our psychiatrist (M.D.). Updated October 12, 2026.