解熱
Conjugation
| Affirmative | Negative | |
|---|---|---|
| Present | 解熱する | 解熱しない |
| Present polite | 解熱します | 解熱しません |
| Past | 解熱した | 解熱しなかった |
| Past polite | 解熱しました | 解熱しませんでした |
| て form | 解熱して | 解熱しなくて |
| ている present | 解熱している | 解熱していない |
| ている polite | 解熱しています | 解熱していません |
| ている past | 解熱していた | 解熱していなかった |
| ている past polite | 解熱していました | 解熱していませんでした |
| Conditional ば | 解熱すれば | 解熱しなければ |
| Conditional たら | 解熱したら | 解熱しなかったら |
| Volitional | 解熱しよう | — |
| Volitional polite | 解熱しましょう | — |
| Potential | 解熱できる | 解熱できない |
| Passive | 解熱される | 解熱されない |
| Causative | 解熱させる | 解熱させない |
| Imperative | 解熱しろ | 解熱するな |
Composed of 解 ('to undo, to dissolve, to relieve') + 熱 ('fever, heat'). Literally 'undoing a fever'. The reading is the on'yomi げ, which is also seen in words like 解毒 ('detoxification') and 解熱剤 ('fever-reducing drug').
USAGE:
解熱 is a medical term, but it appears regularly in everyday life because of its use on cold-medicine packaging and pediatric advice columns. It can be used as a noun, as a する-verb meaning 'to bring down a fever' (transitive: e.g. of a drug acting on fever) or 'for a fever to come down' (intransitive: of a person whose fever subsides).
The most familiar collocation is 解熱剤 or 解熱薬 ('fever reducer'), which is the standard category name for over-the-counter and prescription drugs that reduce fever.
GRAMMAR:
The verb 解熱する is somewhat unusual in that it can be used both transitively (e.g. of medicine acting on a fever) and intransitively (of a person whose fever has come down):
- 薬が熱を解熱する (transitive use, less common)
- 彼は解熱した (intransitive: 'his fever has gone down')
In practice the intransitive use, treating 解熱する as 'to recover from fever', is more common in everyday speech.
COMMON COLLOCATIONS:
- 解熱剤: fever reducer, antipyretic drug
- 解熱薬: fever-reducing medicine
- 解熱作用: antipyretic action (medical)
- 解熱鎮痛剤: fever-reducing painkiller (a common drug category)
- 解熱する: to bring down a fever; for a fever to come down
- 解熱後: after the fever has come down
- 解熱後 24時間: 24 hours after the fever has come down
SIMILAR WORDS:
- 熱が下がる: for a fever to go down — the everyday spoken expression. Less formal than 解熱する.
- 熱冷まし: a fever cooler — colloquial term for a fever-reducing drug (especially the kind given to children); alternatively the cold-pack patches stuck to the forehead.
- 下熱: same as 解熱; an alternative kanji writing, less common in modern usage.
- 解毒: detoxification — same 解 prefix, applied to poisons.
- 鎮痛: pain relief — frequently combined with 解熱 in drug-category names.
- 発熱: fever, the development of a fever — the opposite event.
DOMAIN NOTE:
In Japanese health-care guidance for influenza and infectious diseases, a common rule is that a patient may return to school or work 解熱後 48 時間 ('48 hours after the fever has gone down'). This phrasing is widely used in school notices and corporate sick-leave policies, especially for children.