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.
He fell ill last week.
I suddenly fell ill.
More formal/medical term for 'onset of illness'. Often used in written or clinical contexts.
He fell ill due to stress.
Very formal, often used in medical reports or official documents. Means 'to contract (a disease)'.
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.
I caught a cold.
He fell ill with pneumonia.
Formal/medical term for 'develop symptoms of (a disease)'.
He developed diabetes.
Emphasizing the sudden onset of illness.
When the illness is serious enough to keep someone in bed.
Common in Japanese culture to express illness caused by exhaustion.
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.
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.