Sunan Abi Dawud Book 28, Hadith 119
The Prophet (ﷺ) came to visit Sa'd ibn Ubaydah, and he brought bread and olive oil, and he ate (them). Them). Then the Prophet (ﷺ) said: May the fasting (men) break their fast with you, and the pious eat your food, and the angels pray for blessing on you.
AbulHaytham ibn at-Tayhan prepared food for the Messenger of Allah (ﷺ), and he invited the Prophet (ﷺ) and his Companions. When they finished (food), the said: If some people enter the house of a man, his food is eaten and his drink is drunk, and they supplicate (to Allah) for him, this is his reward.
I came to the Prophet (ﷺ) and his Companions were sitting as if they had birds on their heads. I saluted and sat down. The desert Arabs then came from here and there. They asked: Messenger of Allah, should we make use of medical treatment? He replied: Make use of medical treatment, for Allah has not made a disease without appointing a remedy for it, with the exception of one disease, namely old age.