It is narrated from Umm al-Mu'minin Sayyida Aisha (may Allah be pleased with her) that when the Messenger of Allah (peace and blessings be upon him) would become ill, he would recite «﴿قُلْ هُوَ اللّٰهُ أَحَدٌ﴾» , «﴿قُلْ أَعُوذُ بِرَبِّ الْفَلَقِ﴾» , and «﴿قُلْ أَعُوذُ بِرَبِّ النَّاسِ﴾» and blow over himself. Sayyida Aisha (may Allah be pleased with her) said that when he (peace and blessings be upon him) became very ill, I would recite these surahs and move his (peace and blessings be upon him) right hand over his blessed body for the sake of blessing.