Tirzepatide in Japan: Mounjaro Import Rules

Quick reference

Drug class: GLP-1/GIP dual receptor agonist
Controlled substance: No
Prescription required: Yes
Available locally: Yes, sold as Mounjaro
Storage: Refrigerated (2°C–8°C); do not freeze. Once in use, may be stored below 30°C for up to 21 days.
Max supply to carry: No fixed statutory import cap for non-controlled prescription medication; carry a supply sufficient for your trip plus a reasonable buffer, with documentation.
Key document: Doctor's letter in English (and preferably Japanese) naming the INN, brand, dose, quantity, and diagnosis
Emergency alternative: If your supply is lost, contact a diabetes or endocrinology clinic in a major city; local prescribing is possible but requires a Japanese-licensed physician.

Travelling to Japan with tirzepatide: what changes

Tirzepatide is sold in Japan under the brand name Mounjaro; the US-only brand Zepbound is not marketed here for diabetes. Japan classifies tirzepatide as a prescription-only medicine, not a controlled substance, so no import permit is required. The main practical challenges are cold-chain continuity across a long-haul flight and confirming a local prescribing pathway if your supply runs short.^[1]

Medical disclaimer: This guide is for informational purposes only and does not constitute medical advice. Always consult your prescribing doctor before travelling with medication, particularly regarding supply quantities, storage requirements, and import documentation.

Documentation for travelling to Japan with tirzepatide

Japan's Ministry of Health, Labour and Welfare (MHLW) requires that travellers carrying prescription medicines have documentation confirming the medication is for personal use.^[4] A doctor's letter is sufficient for non-controlled prescription medicines such as tirzepatide; a Yunyu Kakunin-sho (import confirmation certificate) is not required. Carry the letter in both English and, if possible, Japanese.

What your doctor's letter must include

Full name, medication name (tirzepatide and Mounjaro), dose and frequency, quantity carried, diagnosis (one word), doctor's signature and registration number, and clinic letterhead. A Japanese translation is strongly recommended but not legally mandated for personal-use quantities. Notarisation is not required.

How much tirzepatide to bring

Japan does not impose a fixed day-count import cap on non-controlled prescription medicines, but MHLW guidance recommends carrying only a quantity consistent with the trip duration. Bring enough to cover your full stay plus a 20–30% buffer in case of delays. Tirzepatide is a weekly injection, so calculate pens carefully: a four-week trip requires at least five pens to include a buffer.

Split your supply

Pack your primary supply in carry-on luggage and at least one backup pen in your checked bag. If one piece of luggage is lost or delayed, you retain a usable supply. Keep both in original packaging with pharmacy labels visible.

Packing and storing Mounjaro for travel

Mounjaro must be stored refrigerated at 2°C–8°C until first use. According to the EMA-approved product information, an in-use pen may be kept at room temperature below 30°C for up to 21 days. For flights of more than a few hours, use an insulated medical cooling wallet with a gel pack to maintain the cold chain. Never place pens in the aircraft hold, where temperatures can drop below freezing.^[2] See our Mounjaro travel guide for more specific advice on cold-chain management.

Airport security with Mounjaro

Mounjaro prefilled pens are injectable devices and are subject to sharps and liquid rules at security checkpoints. Japan's airport security authority follows rules consistent with those applied at major international hubs: medically necessary liquids and injectable devices are exempt from standard volume restrictions when accompanied by a doctor's letter. Present your documentation proactively at the screening point. Keep pens and cooling wallets together in a single transparent bag for inspection.

Customs and medication import rules for Japan

Japan Customs requires travellers to declare medicines on the incoming passenger declaration form.^[5] Non-controlled prescription medicines for personal use do not require a Yunyu Kakunin-sho (import confirmation certificate).

Tirzepatide is not a controlled substance under Japan's Narcotics and Psychotropics Control Act, so no advance permit is needed. Declare the medication, present your doctor's letter if asked, and keep all pens in original manufacturer packaging with pharmacy labels intact.

Keep original packaging at all times

Customs officers may ask to see the original manufacturer box and pharmacy label to confirm the medication matches your documentation. Do not decant pens into unlabelled cases before arriving at the border. A pharmacy printout showing the dispensing date, quantity, and your name provides additional confirmation.

Mounjaro availability in Japan

Mounjaro received approval from Japan's Pharmaceuticals and Medical Devices Agency (PMDA) and is available at hospital pharmacies and some specialist outpatient pharmacies. A Japanese prescription from a licensed physician is required for any local dispensing. Without insurance, expect to pay approximately ¥25,000–¥40,000 (~$158–$252 / ~€138–€220) per pen at out-of-pocket rates, though prices vary by dose and dispensing facility.^[3]

Finding a doctor who can prescribe Mounjaro in Japan

Tirzepatide is prescribed by endocrinologists and diabetes specialists in Japan. English-speaking physicians are available at international clinics in Tokyo, Osaka, and Yokohama. Use Nomedic's provider search to locate clinics near your destination. A private consultation at an international clinic typically costs ¥8,000–¥15,000 (~$50–$95 / ~€44–€83); hospital outpatient fees may differ depending on the institution.

Search for providers near your destination

Use Nomedic's provider search to find doctors and pharmacies in Japan.

Find a provider

Storing Mounjaro while in Japan

Most hotel rooms and Airbnb properties in Japan include a mini-refrigerator. Confirm refrigeration availability before booking, particularly for rural stays. An in-use pen tolerates below 30°C for up to 21 days, which covers most short trips without additional cooling.

Tokyo's summer temperatures regularly exceed 30°C outdoors, so do not leave pens in a bag exposed to direct heat or sun. Review cold-chain medication guidance before departure if travelling in July or August.

What to do if something goes wrong with your Mounjaro in Japan

If your medication is lost or stolen, file a report with the nearest police station (dial 110) and contact your travel insurer. Obtain a written police report, as insurers require this for reimbursement claims.

If your supply runs out, contact an endocrinology or diabetes outpatient clinic at a major hospital in the nearest city. A Japanese-licensed physician can issue a local prescription for Mounjaro, which can be dispensed at a hospital pharmacy. Bring your original doctor's letter and any remaining packaging to assist the consultation.

“”

For medical emergencies in Japan, call 119 for an ambulance.^[6] The Japan Helpline (0570-000-911) provides 24-hour English-language assistance for foreigners in distress.

Your medication details, ready to share

Nomedic stores your medication name, INN, dosage, and frequency in your IPS, readable by any clinician worldwide.

Go to my record

Frequently asked questions

Is Mounjaro legal in Japan?

Mounjaro (tirzepatide) is legal in Japan and approved by the PMDA. It is a prescription-only medicine and is not a controlled substance, so no import permit is required as long as you carry a valid doctor's letter and a supply consistent with your trip duration.

Can I bring tirzepatide into Japan without a permit?

Yes. Tirzepatide is not a controlled substance under Japan's Narcotics and Psychotropics Control Act, so a Yunyu Kakunin-sho import permit is not required. Carry a doctor's letter, original packaging with pharmacy labels, and declare the medication on your customs form on arrival.

Do I need a doctor's letter to fly with tirzepatide?

A doctor's letter is strongly recommended. Japan Customs may ask for documentation confirming that the medication is for your personal use, and airport security at your departure airport may request evidence that the injectable device is medically necessary. A letter on clinic letterhead naming the INN, brand, dose, and quantity covers both requirements.

Is Mounjaro available at pharmacies in Japan?

Mounjaro is available in Japan at hospital-affiliated pharmacies with a prescription from a Japanese-licensed physician. Retail pharmacy availability outside major cities is limited, so do not rely on being able to purchase it locally without prior arrangement.

Is Zepbound available in Japan?

Zepbound is not marketed in Japan for diabetes, but is specifically approved and marketed for obesity. The same active ingredient, tirzepatide, is sold in Japan exclusively under the Mounjaro brand name. If you currently use Zepbound, your medication is the same compound and the import rules described in this guide apply equally.

What if I run out of Mounjaro while in Japan?

Visit an endocrinology or diabetes outpatient clinic at a major hospital. A Japanese physician can issue a local prescription for Mounjaro, which can then be dispensed at the hospital pharmacy. Bring your original documentation to support the consultation.

How should I store Mounjaro during summer travel in Japan?

Unopened pens require refrigeration at 2°C–8°C. An in-use pen can be kept at below 30°C for up to 21 days, but Tokyo's summer outdoor temperatures regularly exceed this threshold. Store pens in the hotel mini-refrigerator when not in use and carry them in an insulated medical wallet when moving between locations.

Related practical guide

GLP-1 Medications Abroad: Cold Chain Failures, Customs Traps and Approval Gaps

Your Ozempic pen survives the flight but gets confiscated at the border. Here is how cold chain failures, customs rules, and approval gaps catch GLP-1 travellers off guard.

Read the practical guide →

Sources

More guides in Japan

Tirzepatide in other countries

Medication🇪🇸 Spain

Country guide

CountryHealthcare in Japan

Tirzepatide in Japan: Mounjaro, Brands and Import Rules