Sahih Bukhari

Narrated Ibn `Abbas and `Aisha:Abu Bakr kissed (the forehead of) the Prophet (ﷺ) when he was dead. `Aisha added: We put medicine in one side of his mouth but he started waving us not to insert the medicine into his mouth. We said, ""He dislikes the medicine as a patient usually does."" But when he came to his senses he said, ""Did I not forbid you to put medicine (by force) in the side of my mouth?"" We said, ""We thought it was just because a patient usually dislikes medicine."" He said, ""None of those who are in the house but will be forced to take medicine in the side of his mouth while I am watching, except Al-`Abbas, for he had not witnessed your deed