From Sahih Bukhari (Hadith 5743):
Narrated `Aisha:The Prophet (ﷺ) used to treat some of his wives by passing his right hand over the place of ailment and used to say, "O Allah, the Lord of the people! Remove the trouble and heal the patient, for You are the Healer. No healing is of any avail but Yours; healing that will leave behind no ailment
Reference: Bukhari 5743