Musnad Ahmad 1153:2224

Yunus narrated to us, Hammad—meaning Ibn Zayd—narrated to us, from ‘Amr—meaning Ibn Malik—from Abu al-Jawza’, that ‘Aisha said: I used to seek refuge for the Messenger of Allah (peace and blessings of Allah be upon him) with a supplication when he was ill, which Gabriel used to use to seek refuge for him and supplicate for him with when he was ill. She said: So I went to seek refuge for him with it: "Remove the harm, O Lord of the people. In Your hand is the cure; there is no healer but You. Grant a cure that leaves behind no illness." She said: So I went to supplicate for him with it during his illness in which he passed away, and he said: "Lift it away from me." He said: "For it only used to benefit me during the [previous] period."