Translation guide
Describes loose, watery stools. In Japanese, the most common and neutral term is 下痢 (げり). There are also more casual or euphemistic expressions, as well as medical terms.
The standard, neutral way to say 'diarrhea' in most situations, including medical contexts.
The most common and direct translation. Used in both casual and formal settings.
I've had diarrhea since yesterday.
If you have symptoms of diarrhea, drink plenty of fluids.
A softer, more euphemistic way to say 'have loose bowels'. Common in everyday conversation.
I have a bit of an upset stomach (diarrhea).
Verb phrase meaning 'to have diarrhea'. Slightly more direct than お腹がゆるい.
I ate something weird and got diarrhea.
Specifically refers to watery diarrhea. More descriptive and somewhat technical.
The watery diarrhea won't stop.
Very informal ways to talk about diarrhea, often used among friends or in humorous contexts.
Terms used in medical settings or formal writing.
While 'the runs' is a common English euphemism, there is no direct equivalent in Japanese. Use 下痢 or お腹がゆるい instead. The slang 下痢ピー is the closest in tone but is very informal.
In polite settings, you can soften the statement by using お腹の調子が悪い (stomach condition is bad) or お腹がゆるい. Directly saying 下痢です is acceptable but can sound blunt.
I drank too many cold drinks and got diarrhea.
Take medicine for diarrhea.