From Sahih Bukhari (Hadith 6886):
Narrated `Aisha:We poured medicine into the mouth of the Prophet (ﷺ) during his ailment. He said, "Don't pour medicine into my mouth." (We thought he said that) out of the aversion a patient usually has for medicines. When he improved and felt better he said, "There is none of you but will be forced to drink medicine, except Al-`Abbas, for he did not witness your deed
Reference: Bukhari 6886