Ruqya is the healing of many conditions through using the prophetic prescriptions and Qur'an to bring about cure with the permission of Allah Ta'ala.
A believer should use the means of ruqya as divine assistance to help with eradicating sihr and sickness which are linked to sihr. One can use ruqya for any sickness too, having full faith in the command of Allah swt.
The greatest ruqya are Surah Fatiha and the mu'awwathatain - that is sura falaq and surah naas.
"Qul Huwal Laahu Ahad"