"Fever is from the heat of the Hell, so cool it with water."

Another chain reports similar narration.
Jami` at-Tirmidhi Book 28, Hadith 39
← Previous Hadith "Fever is from the agitation of the Fire, so cool it with water."

Jami` at-Tirmidhi Book 28, Hadith 38 Next Hadith → "For fever, and all pains, the Prophet (S.A.W) would teach them to say: Bismillahil-Kabir; a'udhu billahil-'Azimi min sharri kulli 'irqin na'arin, wa min sharri harrin-nar. (In the name of Allah the Great, I seek refuge with Allah the Magnificent from the evil of every gushing vein, and from the evil of the heat of the Fire)"

Jami` at-Tirmidhi Book 28, Hadith 40