Can I bring melatonin to Japan?

By Natsuko Shibata, pharmacist licensed in Japan · Updated 2026-09-25

The short answer

Yes, for your own use and within limits. The catch is that Japan doesn't see melatonin as a supplement. It's on the health ministry's list of substances that are treated as medicines regardless of how they're labeled abroad, so a bottle of melatonin gummies is, at the border, a medicine.

That puts it under the ordinary personal-import limits:

  • Two months' supply is the most you can bring in as a non-prescription medicine without an Import Confirmation.
  • Japan's only approved melatonin product is prescription-only, and we couldn't find a clear statement of whether a foreign melatonin supplement is judged by the prescription line (one month) or the general line (two months). Bringing one month's supply avoids the question.
  • Above whatever line applies, you need an Import Confirmation (Yunyu Kakunin-sho), applied for online before you travel. The health ministry's own statistics show melatonin turning up every year among products people apply for.

For the general rules, see Bringing your medication to Japan.

How the amount is judged

The limit is by dose as written on the label, so a bottle of 60 tablets labeled "one at bedtime" is a 60-day supply, while a bottle of 120 labeled the same way is four months and needs an Import Confirmation. Large "value size" bottles are the usual problem. If you'd take two tablets a night, the label still decides.

Keep it in the original bottle with the label; a bag of loose gummies can't be assessed and is more likely to be held.

Melatonin isn't a controlled substance, so there's no permit, no doctor's certificate requirement and no "prohibited" category. In practice, a bottle over the limit is usually held at customs, or you're asked to apply for the confirmation after the fact. Outcomes vary, and that isn't a guarantee.

Why you can't buy it in Japan

Because melatonin is a medicine here, it can't be sold as a supplement, and there is no over-the-counter melatonin product. The one approved product, Melatobel (melatonin granules), is prescription-only and approved for sleep problems in children with neurodevelopmental conditions, not for adults or jet lag. Prescribing it to an adult for sleep would be off-label, and whether to do that is a decision left to the prescribing doctor.

What Japanese pharmacies do sell over the counter for occasional sleeplessness are antihistamine-based sleep aids (diphenhydramine, the same ingredient as in some Western "PM" products). Prescription sleep medicines here include the orexin antagonists suvorexant (Belsomra) and lemborexant (Dayvigo), and ramelteon (Rozerem), which acts on melatonin receptors. Which, if any, a doctor uses is their decision, and this page doesn't compare them.

Before you travel

  • Bring one month's supply at most, in the original labeled bottle.
  • Leave the value-size bottle at home, or apply for an Import Confirmation before you fly.
  • Don't expect to buy melatonin in Japan.
  • Ordering melatonin online after you arrive doesn't get around the limit. The same personal-import rule applies to a parcel, and one over the limit is held by customs until you apply for an Import Confirmation.

The Japan Medication Entry Check

If melatonin is one of several products on your list, the Japan Medication Entry Check is a written review by a licensed pharmacist in Japan. We go through each item, tell you which category it falls into and what paperwork it needs, with links to the official pages, and explain how that category is generally handled here. You file the Import Confirmation yourself; we don't file it for you. It isn't an official ruling, and it isn't a decision about your treatment. The price is US$200, with additional items at US$20 each.

See the Entry Check — US$200

Official sources

I am a pharmacist. I cannot diagnose you or tell you to stop a medicine your doctor has prescribed.