Here is a dua from Quran that must be recited whenever you feel you are being attacked evil suggestions (waswaas of shaitan). It is becoming more and more important for a believer to be on guard when it comes to creating thoughts in their head. Evil suggestions can haunt a person, giving them the impression that they are their own thoughts and this is what keeps many people crippled mentally.
Reference of the dua: Surah Al Mominun, Chapter 23, Verse no. 97-98
Transliteration of the Dua:
"Rabbi Aaoozu Bika Min Hamazaat-ish-Shayateeni Wa Aaoozu-bika Rabbi Ain-Yahzuroon"
English Translation of the Dua"
"My Lord! I seek refuge with You from the whisperings of the Shayatin (devils). And I seek refuge with You, My Lord! lest they should come near me."
Recite this dua as often as you can in order to fight off shaitan waswasa. Another powerful beenfit of reciting dua is that it keeps you safe from black magic, djinn possessions and evil eye. In order to get th maximum benefit from this dua, you can set a certain number of recitation (say 200 to 300). This will discipline your mind and you will focus on dwelling on the meaning of the dua.