Generic Drugs in Japan: Brand or Kohatsuhin at the Counter

When a Japanese pharmacist asks whether you want senpatsuhin (先発品, the brand-name original) or kohatsuhin (後発品, the generic), the generic is almost always the cheaper choice for the identical medicine. Japan sets a national list price for every approved drug, and a kohatsuhin's price is fixed lower than its senpatsuhin equivalent - so since your insurance co-pay is a percentage of that price, choosing generic medicine in Japan lowers what you actually pay at the counter. The choice is generally yours to make; say kohatsuhin de (generic, please) or senpatsuhin de (brand-name, please) when asked, or ask your pharmacist directly if you're not sure a generic exists for your prescription.

後発品 (kohatsuhin), literally 'later-developed product,' is Japan's term for a generic drug - approved after the original's patent protection ends, built on the same active ingredient at the same dose. 先発品 (senpatsuhin), 'first-developed product,' is the original brand-name version that reached the market first. Neither term implies a difference in effectiveness; kohatsuhin simply arrived later and is priced accordingly. You'll sometimes hear the loanword ジェネリック (jenerikku) used the same way as kohatsuhin in everyday conversation.

Japan doesn't leave drug pricing to individual pharmacies - every approved medicine, brand or generic, is assigned a fixed national price, and a kohatsuhin is set lower than the senpatsuhin it's based on. What you pay isn't the full price either way: your health insurance co-pay is a percentage of it, typically 30 percent for most adults, with a lower share for children and people age 70 and older (the health guide covers the full breakdown). Because that percentage applies to whichever list price you picked, choosing the brand-name original when an identical generic exists means paying a percentage of a higher number for the same medicine - month after month, if it's a repeat prescription.

You don't need to wait for the pharmacist to bring it up. If you'd rather have the generic, say 後発品にしてください (kohatsuhin ni shite kudasai), or simply 'kohatsu de onegaishimasu.' If you specifically want the brand-name original, say 先発品でお願いします (senpatsuhin de onegaishimasu). If you're unsure whether a generic exists for what you've been prescribed, ask: 'kono kusuri no kohatsu wa arimasu ka' (is there a generic version of this medicine). A newly approved drug generally won't have a generic yet, since a kohatsuhin can only be developed once the original's patent protection has expired - your pharmacist can tell you on the spot whether that applies to you.

For the rest of the process - what to bring, how fast you need to move, how the co-pay actually gets charged - see how to fill a prescription in Japan. If you're setting up healthcare here for the first time, the moving to Japan guide covers enrolling in insurance in the first place.