Ayesha reported that the Prophet ﷺ used to recite the Muawwidhat over himself and blow into his hands.Ayesha said, "When he ﷺ fell ill, I would recite them over him and wipe him with his own hand, hoping for the blessing of his hand."
حدثنا أبو سلمة الخزاعي قال أخبرنا مالك عن ابن شهاب عن عروة
أن النبي ﷺ كان يقرأ على نفسه المعوذات وينفث قالت عائشة فلما اشتكى ﷺ جعلت أقرأ عليه وأمسحه بكفه رجاء بركة يده
Its isnad is sahih. Bukhari narrated it, 8/131, no. 4439, in the Book of Maghazi, and Muslim, 4/723, no. 2192, in the Book of Salam, and Abu Dawud, 4/15, no. 3902, and Ibn Majah, 1166, no. 3529, both in the Book of Medicine, and Nasai in Amal al-Yawm wal-Layla, no. 1009, and Abd bin Humayd, 429, no. 1474, in al-Muntakhab.