Ruqyah in Islam is the recitation of the Quran, seeking of refuge in Allah, remembrance and supplications that are used as a means of treating sicknesses and other problems as the Quran is a source of healing.
It was narrated that ‘Aisha (may Allah be pleased with her) said: When the Messenger of Allah (peace and blessings of Allah be upon him) was ill, he would recite al-Mi’wadhatayn over himself and spit drily. When his pain grew intense, I recited over him and wiped him with his own hand, seeking its barakah (blessing).”
(Bukhaari, 4728; Muslim, 2192)
With regard to the dua’ that is prescribed for the Muslim to say if he wants to recite ruqyah for himself or for someone else, there are many such dua’s, the greatest of which are al-Faatihah and al-Mi’wadhatayn (i.e. Last Three Surah of the Qur’an).