Aisha reported that whenever the Messenger of Allah ﷺ fell ill, he would recite the protective surahs over himself and blow gently. When his illness grew severe, I would recite them over him and wipe him with his own hand, hoping for its blessing.
أن رسول الله ﷺ لو كان إذا اشتكى يقرأ على نفسه بالمعوذات وينفث، فلما اشتد وجعه كنت أقرأ عليه، وأمسح عنه بيده رجاء بركتها.
Bukhari narrated it in Fadail al-Quran (5016), and Muslim in al-Salam (2192:51), both through the route of Malik, from Ibn Shihab, from Urwa, from Ayesha, who said, and then she mentioned it.