1. What changed (effective Nov 12, 2026)
South Korea's Ministry of Food and Drug Safety revised its personal carry-on prescription drug import criteria effective November 12, 2026. The key change: obesity-treatment medications (Mounjaro, Wegovy, and other GLP-1 class drugs) that Korean Customs had routinely restricted on grounds of difficulty verifying manufacturing and distribution safety are now permitted for personal carry-on import, provided they were properly prescribed and purchased at an overseas medical institution.
Significant unofficial traffic was already happening because of the large gap between Korea's out-of-pocket prescription price and overseas prices. The reform formalizes a legal pathway rather than creating new demand.
① Quantity is now specified: Base limit 6 vials, up to 3-month supply (or 12 pens for once-weekly injectables) is written into the criteria. ② Price gap now acknowledged publicly: ₩350,000/month in Korea vs. ¥85,000-172,000 abroad is cited in official coverage. ③ Mail and e-commerce still prohibited: Patient must personally obtain prescription overseas and personally carry it in.
Why now
Korean and international outlets (Kyunghyang Shinmun, Korea JoongAng Daily, Seoul Economic Daily) point to the Korea-Japan price gap as the immediate driver. Korea's private prescription price is reported at roughly ₩350,000/month, versus around ¥85,000 (~₩85,000) in Japan — about a 4x gap. Japan is explicitly named as the primary destination for Korean cross-border prescription traffic.
In Korea, Mounjaro is approved only for type 2 diabetes; the obesity indication is under MFDS review as of November 2026. Non-diabetic patients can only receive prescriptions off-label at private clinics at premium rates. Japan, by contrast, has approved Mounjaro for obesity treatment and maintains stable supply across all six Ateos auto-injector doses (2.5/5/7.5/10/12.5/15mg).
2. The quantity limit, precisely
The quantity limit in the MFDS announcement should be read with three parallel benchmarks:
| Benchmark | Quantity | Applied to Mounjaro |
|---|---|---|
| Base limit | 6 vials | Mounjaro is packaged as auto-injector pens (Ateos), not vials, so the pen benchmark below applies |
| Per-dosage limit | Up to 3-month supply | Up to 3 months per the dosage schedule written on the Japanese prescription |
| Once-weekly injection pens | Up to 12 pens | Mounjaro Ateos = 1 pen × once-weekly × 12 weeks = 3 months |
Each Mounjaro Ateos pen contains one weekly dose at 2.5/5/7.5/10/12.5/15mg. Japanese physicians may prescribe up to a 6-month supply in a single prescription, but given the Korean customs limit, a 3-month supply (12 pens) is the practical travel-size window.
Patients mid-titration (e.g., 2.5mg → 5mg → 7.5mg) can carry a 3-month supply made up of multiple dose strengths. For example: "2.5mg × 4 weeks + 5mg × 4 weeks + 7.5mg × 4 weeks = 12 pens." Ask that the English prescription list weeks-per-dose explicitly so customs can match quantities. eHealth Clinic Shinjuku writes titration schedules into the English prescription by default.
3. Required documents and customs clearance
The reform did not just change the quantity — it conditioned import on proof of proper prescription and purchase. Being within the quantity limit alone does not guarantee clearance; documents are essential.
Document checklist
Physician signature, issue date, patient name matching passport, drug name (Mounjaro / Tirzepatide), dose, and administration schedule. Issued by eHealth Clinic Shinjuku automatically.
States the medication is for personal medical use (for personal medical use), for weight management or obesity treatment. Issued by eHealth Clinic Shinjuku on request.
Outer Mounjaro carton and individual pen labels kept intact so airport security and customs can clearly identify the medication.
At Incheon/Gimpo/Gimhae, use the red (declare) channel. Declare the medication proactively and present the documents. Non-declaration risks adverse consequences if detected.
Useful customs-counter phrases (Korean)
If the customs officer only speaks Korean, these phrases help:
- “개인 치료용 처방약을 신고합니다.” (I am declaring prescription medication for personal use.)
- “일본 의사가 처방한 마운자로입니다.” (This is Mounjaro, prescribed by a doctor in Japan.)
- “처방전과 진단서입니다.” (Here is my prescription and medical certificate.)
- “수량은 3개월분 한도 이내입니다.” (The quantity is within the 3-month supply limit.)
4. Maintaining the 2-8°C cold chain
Mounjaro is a biologic requiring 2-8°C refrigeration before first use. Extended exposure to room temperature (above 25°C) can degrade tirzepatide. Maintaining the cold chain across Japan → Korea is the single biggest operational challenge.
Four-step cold chain
eHealth Clinic Shinjuku delivers via Yamato Cool TA-Q-BIN (refrigerated courier) maintaining 2-8°C to the hotel. Hotel staff refrigerate until check-in retrieval.
Ask the hotel to freeze gel packs/ice packs in their freezer overnight. Prepare insulated pouch.
Pack insulated pouch + frozen gel packs + Mounjaro pens together as cabin baggage only. Never checked luggage — cargo-hold temperatures can drop below freezing and damage tirzepatide. Present prescription at security if asked.
Clear customs declaration at Incheon/Gimpo → immediately move to home or hotel refrigerator (2-8°C). For long drives, keep the insulated pouch. Immediate refrigeration at home is essential.
Store the insulated pouch at your feet rather than in the overhead bin. Overhead compartments can warm during flight, while under-seat storage is more thermally stable. The 2.5-hour ICN-NRT flight is easily within a single frozen gel pack's cooling window.
5. The process in Japan
The eHealth Clinic Shinjuku prescription flow for Korean residents:
Standard prescription flow (Korean residents)
Book at diet.ehealthclinic.jp/ko (Korean) or /en (English). Korean-issued credit cards accepted.
90-day visa-free entry. No time difference. Multiple LCC/FSC daily flights.
Dr. Hoichi Amano, Harvard T.H. Chan graduate, consults directly in English or Mandarin. Google Meet real-time translation supports Korean. Covers BMI, history, dose plan, side effects.
English prescription + English medical certificate (personal use) issued automatically. Korean customs guide included.
Within 24 hours of consultation, Yamato Cool TA-Q-BIN delivers to hotel at 2-8°C. Or same-day pickup from Shinjuku clinic (1-min walk from Shinjuku-sanchome Station).
Bring English prescription + certificate, use red channel, declare, present documents.
Same physician's online video follow-ups for dose adjustment and side-effect management. Google Meet translation supports Korean. Next trip or online re-consultation after ~3 months.
6. Cost comparison (KRW)
Total cost for a one-trip 3-month supply, compared to a Korean private clinic. Savings expand significantly at higher doses.
| Scenario (3 months, 2.5mg) | Drug cost | Other costs | Total |
|---|---|---|---|
| Korean private clinic Private out-of-pocket, 2.5mg × 3 months |
~₩1,050,000 (per media reports) | Consultation ₩50,000-150,000 | ~₩1,100,000-1,200,000 |
| Japan 2-3 night trip (LCC) 2.5mg × 3 months + round-trip flights + hotel |
~₩515,000 (3 months) | Flights ₩300,000 + hotel 2 nights ₩200,000 + consultation ₩80,000 | ~₩1,095,000 |
| Japan 2-3 night trip (FSC) 2.5mg × 3 months + round-trip flights + hotel |
~₩515,000 (3 months) | Flights ₩500,000 + hotel 2 nights ₩300,000 + consultation ₩80,000 | ~₩1,395,000 |
At the 2.5mg starting dose on a budget LCC trip, total cost is roughly comparable to a Korean private prescription, but you also get a Tokyo visit. Savings grow at higher doses (7.5mg and above) because Korea's per-dose markup is steeper than Japan's. 7.5mg in Korea is roughly ₩500,000-700,000/month versus roughly ₩250,000-300,000 in Japan.
For patients planning 6+ months of therapy, two Japan trips (two 3-month supplies) or one trip for a Japan bundle followed by Korean maintenance are both viable. eHealth Clinic Shinjuku also offers a 6-month bundle with roughly 17-21% discount, which can beat two separate 3-month trips depending on flight costs.
7. What this reform does not change
- Mail and e-commerce remain prohibited: The patient must obtain the prescription overseas personally and carry it in personally. Third-party couriers, mail orders, and online purchases are not covered by this reform.
- Commercial import remains illegal: Personal treatment use only. Resale, proxy-purchase re-export, or commercial import violate Korea's Pharmaceutical Affairs Act and customs law.
- Over-quantity imports still require prior approval: Quantities exceeding 3 months require advance clearance; excess seizure/return is standard if unapproved.
- Narcotics and psychotropics are excluded: This liberalization does not extend to controlled substances. Mounjaro and Wegovy are not controlled substances.
- Korean domestic prices are not reduced: This is an import rule change, not a domestic price regulation.
8. Frequently asked questions
Can a first-time patient get a 3-month supply immediately?
Yes. A Japanese physician may prescribe up to 6 months at first visit based on clinical judgment. However, patients on dose titration (2.5mg → 5mg → 7.5mg) often need staged scheduling, so eHealth Clinic Shinjuku typically recommends a 3-month titration schedule on first visit.
Is a medical certificate strictly required in addition to the prescription?
The MFDS announcement specifies "properly prescribed and purchased" evidence. In many cases a prescription alone is sufficient. For reliable clearance, however, we recommend both an English prescription and an English medical certificate (stating personal use). eHealth Clinic Shinjuku issues both — prescription automatically, certificate on request.
Can a companion carry Mounjaro in on my behalf?
No. The reform applies only when the prescription-holder personally carries the medication. Family members or friends cannot receive the prescription or carry the medication on your behalf. Each patient must import under their own prescription.
Do I need to declare Japan-prescribed medication at Korean customs?
Yes. Check the "medication" item on the customs declaration form, use the red (declare) channel, and present your English prescription and medical certificate. Non-declaration risks adverse consequences if detected.
Does the same rule apply to Wegovy (semaglutide)?
Yes. Wegovy (semaglutide) is also covered. Its FlexTouch pen is also once-weekly, so the same up-to-12-pens (= 3-month supply) limit applies. eHealth Clinic Shinjuku primarily prescribes Mounjaro because SURMOUNT trial data show roughly 20% average weight loss versus roughly 15% for Wegovy.
Are frozen ice packs allowed in cabin baggage?
Major Korean airlines (Korean Air, Asiana, Jeju Air, T'way) all permit medical cold-chain ice packs in cabin baggage. However, if not fully frozen (solid state) at security, they may be treated as liquid. Freeze packs overnight in the hotel's freezer, and use airport-lounge ice if a top-up is needed before boarding.
How do I book with eHealth Clinic Shinjuku?
Book at diet.ehealthclinic.jp/ko (Korean) or /en (English). Choose online video (while in Japan, with hotel delivery) or in-person (1-minute walk from Shinjuku-sanchome Station). Korean-issued cards (Visa, Mastercard, JCB, Amex) accepted. Dr. Hoichi Amano, Harvard T.H. Chan graduate, consults directly in English or Mandarin Chinese.
Sources
- South Korea Ministry of Food and Drug Safety (식약처) revised "Personal Carry-On Prescription Drug Import Criteria," effective 2026-11-12
- Kyunghyang Shinmun: "Mounjaro·Wegovy prescribed overseas now allowed to be brought into Korea starting today" (2026-11-12)
- Korea JoongAng Daily: "Korea allows travelers to bring prescribed Mounjaro from Japan" (2026-11-12)
- Seoul Economic Daily: "Korea to Allow Travelers to Bring In Weight-Loss Drugs From Thursday" (2026-11-11)
- Mainichi Shimbun: "韓国、マンジャロの持ち込み容認 日本で買い付け、さらに増加か" (2026-11-12)