We administered medicine to the Messenger of Allah ﷺ by force during his illness, and he gestured that we should not do so. We thought it was simply the aversion of a sick person to medicine. When he regained consciousness, he said, "Did I not forbid you from forcing medicine into my mouth?" He then said, "Let no one among you escape having medicine forced into his mouth, except Abbas, for he was not present with you."
حدثنا يحيى عن سفيان حدثني موسى بن أبي عائشة عن عبيد الله بن عبد الله
لددنا رسول الله ﷺ في مرضه فأشار أن لا تلدوني قلت كراهية المريض الدواء فلما أفاق قال ألم أنهكم أن لا تلدوني قال لا يبقى منكم أحد إلا لد غير العباس فإنه لم يشهدكن
Its isnad is sahih. Bukhari related it in 8/147 no. 4458, Fath, in the chapters on military expeditions. Muslim related it in 4/1733 no. 2213, in the chapter on greetings. And Tirmidhi related it in 4/288 no. 2047, in the chapter on medicine, and he said, hasan gharib.