For one afflicted by whisperings in prayer or recitation1 du'a

(Say:) I seek refuge in Allah from Satan the outcast(then blow with a little spittle to your left). ...

Reference:Muslim 4/1729.Hisnul Muslim 138

أَعُوذُ بِاللَّهِ مِنَ الشَّيطَانِ الرَّجِيمِ وَاتْفُلْ عَلَى يَسَارِكَ (ثلاثاً)

Transliteration

A`ūdhu billāhi minash-shayṭānir-rajīm.

Translation

(Say:) I seek refuge in Allah from Satan the outcast(then blow with a little spittle to your left). (Do this three times reciting in Arabic.)