Before you take medicine abroad, check the destination's rules: cold and cough medicines that contain pseudoephedrine or codeine, and sleeping pills, psychiatric drugs, and strong painkillers, should be in the original pack, with a prescription or a doctor's note, and only in the amount you will use yourself

Cold and cough medicines with more than 10% pseudoephedrine or more than 1% codeine are regulated in Japan as a stimulant raw material or as a narcotic, and you have to apply for permission ahead of time. If you take more than a month's supply of sleeping pills, Japan also requires you to get a permit in advance, and Singapore requires an advance application for a medicine that contains a controlled ingredient. Carry the original pack and a doctor's note, and carry only what you will use yourself, and you can avoid having the medicine confiscated, a fine, or even a criminal sentence.

Cost

No money. Check the destination's official site once before you leave. It takes a few minutes. If you need to take a controlled drug, you also make an extra trip to the hospital for a certificate, and you apply about 2 weeks ahead.

Benefit

Japan regulates medicines by ingredient. A medicine with more than 10% pseudoephedrine counts as a "stimulant raw material." A medicine with more than 1% codeine counts as a narcotic. Both require a permit from the Narcotics Control Department of the Ministry of Health, Labour and Welfare before entry, at least 14 days ahead. You must carry the medicine yourself. You cannot mail it, and you cannot have a family member carry it for you. For a psychiatric drug such as diazepam or triazolam, a supply of up to a month does not need an application. Ordinary medicines have limits too: a prescription medicine within a month's supply, and other medicines within a 2-month supply. Above that, you first get an "import confirmation certificate." The reminder from the Chinese embassy in Japan says, in the original wording, that illegally carrying medicines and similar items into Japan means "the violator will be fined, detained, or even sentenced, and the prohibited items will be confiscated." The rule of Singapore's Health Sciences Authority (HSA) is: a medicine that does not contain a controlled ingredient, at most a 3-month supply. Carry a copy of the prescription or of a doctor's letter. Keep the medicine in the original pack, with the pharmacy label on it. A medicine that contains a controlled ingredient needs approval applied for at least 2 weeks ahead. A supply of more than 3 months may not be brought in at all, and neither may a medicine in the form of chewing gum. Carrying medicine for someone else is limited to a direct relative's own prescription medicine. Medicine that does not comply will be confiscated, and you may also face enforcement. On the Chinese side, the Customs Law requires that articles an individual carries in or out be "limited to personal use and a reasonable quantity." Narcotic drugs and the first category of psychotropic drugs may be carried, within the maximum amount of a single prescription, on a hospital diagnosis certificate and an identity document. Customs releases them on the principle of personal use and a reasonable quantity.

Notes

The rules change, and they differ by country. This book only writes how to check. Before you leave, look at the official site of the destination's health department or customs, or the consular advisory of the Chinese embassy there. The Japan and Singapore rules above were checked against the official sites on October (10) 14, 2026. Whether a medicine contains these ingredients is on the ingredient list in the leaflet. If you are not sure, ask the doctor who prescribed it. The best person to carry the medicine is the person who takes it. Singapore allows you to carry only a direct relative's own prescription medicine for that relative. This is the same point as section 8, item 29 (do not carry things for strangers). Photograph the prescription and the box and keep a copy. For how to store it, see item 7 of this section (photograph a copy and keep it in the cloud).

Sources · 8

1. 日本厚生劳动省麻药取缔部. Application Guidance（携带含管制成分的药品出入境）：「When you enter/leave Japan carrying your medicine containing controlled substances in Japan for your own medical use, you need to get a permission in advance.」「You should apply at least 14 days prior to your travel.」「you can't send your medicine to/from Japan and you can't also entrust carrying it to other people, such as your family.」. ncd.mhlw.go.jp/en/application2.html
2. 日本厚生劳动省麻药取缔部 (2024). Controlled Substances List（2024 年 12 月 12 日版）：「Ephedrine, Pseudoephedrine (Any substances containing 10% or less of ephedrine or pseudoephedrine are excluded.)」「Codeine … (Any substances containing 1% or less of codeine or its salt are excluded.)」. ncd.mhlw.go.jp/dl_data/keitai/cotrolled_subst…
3. 日本厚生劳动省. Information for those who are bringing medicines for personal use into Japan：「Poison, Deadly poison, Prescription drug : Up to 1 month supply」「Other Drugs, Quasi drugs : Up to 2 month supply」. mhlw.go.jp/stf/seisakunitsuite/bunya/kenkou_i…
4. 日本厚生劳动省. 医薬品等の個人輸入について：「医療用向精神薬(ジアゼパム、トリアゾラム等)の携帯輸入: 1ヶ月分を超える分量又は注射剤を携帯輸入する場合は、事前に輸入確認証を取得する必要があります」. mhlw.go.jp/stf/seisakunitsuite/bunya/kenkou_i…
5. 中国驻日本大使馆 (2018). 来日本旅行请勿携带违禁品. jp.china-embassy.gov.cn/jbwzlmnew/lszcnew/LSB…
6. Health Sciences Authority, Singapore. Bringing in personal medications：「You may bring up to 3 months' supply if no approval is needed and the medication is not prohibited.」「Please note that imports of quantities exceeding 3 months' supply are not allowed.」「Failure to comply will result in your medication being confiscated or enforcement action may be taken.」. hsa.gov.sg/travelling-with-medication-and-med…
7. 全国人大常委会 (2021 年修正). 海关法（第四十六条）. flk.npc.gov.cn/detail?id=ff8081817ab22b8a017a…
8. 国务院 (2024 年第三次修订). 麻醉药品和精神药品管理条例（第四十四条）. flk.npc.gov.cn/detail?id=ff8081819c230ff2019c…