The Book of Greetings
حَدَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنِ ابْنِ شِهَابٍ، عَنْ عُرْوَةَ، عَنْ عَائِشَةَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم كَانَ إِذَا اشْتَكَى يَقْرَأُ عَلَى نَفْسِهِ بِالْمُعَوِّذَاتِ وَيَنْفُثُ فَلَمَّا اشْتَدَّ وَجَعُهُ كُنْتُ أَقْرَأُ عَلَيْهِ وَأَمْسَحُ عَنْهُ بِيَدِهِ رَجَاءَ بَرَكَتِهَا .A'isha reported that when Allah's Messenger (ﷺ) fell ill, he recited over his body Mu'awwidhatan and blew over him and when his sickness was aggravated I used to recite over him and rub him with his band with the hope that it was more blessed
From Sahih Muslim, whose reports the scholars accept as authentic.