Translation guide
How to express becoming sick or unwell in Japanese, from casual to formal situations.
The most common and neutral way to say someone becomes ill.
The standard, neutral expression for 'to fall ill' or 'to get sick'. Suitable for most situations.
彼は先週病気になりました。
He fell ill last week.
I suddenly fell ill.
More formal/medical term for 'onset of illness'. Often used in written or clinical contexts.
彼はストレスで発病した。
He fell ill due to stress.
Very formal, often used in medical reports or official documents. Means 'to contract (a disease)'.
インフルエンザに罹患した。
He contracted influenza.
When you want to specify the disease or condition.
The most common way to say 'to come down with (a disease)'. Use the disease name before にかかる.
風邪にかかった。
I caught a cold.
彼は肺炎にかかった。
He fell ill with pneumonia.
Formal/medical term for 'develop symptoms of (a disease)'.
彼は糖尿病を発症した。
He developed diabetes.
Emphasizing the sudden onset of illness.
Literally 'suddenly condition becomes bad'. Very natural for describing a sudden illness.
彼は急に具合が悪くなった。
He suddenly fell ill.
Means 'to be taken suddenly ill'. Slightly more formal.
旅行中に急病になった。
I fell ill during the trip.
When the illness is serious enough to keep someone in bed.
Means 'to be laid up with illness', 'to be sick in bed'. Very common.
彼は一週間病気で寝込んでいた。
He was ill in bed for a week.
Literary/formal expression for 'to be confined to a sickbed'.
彼は長い間病床に伏している。
He has been ill in bed for a long time.
Common in Japanese culture to express illness caused by exhaustion.
Literally 'collapse from overwork'. Often used when someone falls seriously ill due to work stress.
彼は過労で倒れた。
He fell ill from overwork.
Means 'to ruin one's health' or 'to get sick' often due to lifestyle or stress. Very common.
働きすぎて体調を崩した。
I fell ill from working too much.
病気になる is a direct statement of becoming ill. 体調を崩す implies a more gradual decline in health, often due to lifestyle, and is slightly softer/euphemistic.
最近体調を崩しやすい。
I tend to get sick easily these days.
English 'fall ill' uses 'fall', but Japanese does not use 落ちる (ochiru) for becoming sick. Use 病気になる or other expressions above.