From Sahih Muslim (Hadith 5709):
A'isha reported Allah's Messenger (ﷺ) as saying:When Allah's Messenger (ﷺ) visited the sick he would say: Lord of the people. remove the disease, cure him, for Thou art the great Curer, there is no cure but through Thine healing Power, which leaves nothing of the disease
Reference: Muslim 5709