There are two types of Ruqyah , that which is prescribed in the Quran and Sunnah and the Ruqyah which contains shirk.

1. Ruqyah Ash Shariah – this Ruqyah is the type that is prescribed in the Quran and the Sunnah. The conditions are ; that the ruqyah must be performed with the words of Allah – ayahs from the Quran , invocations and the beautiful names of Allah. That the ruqyah must be performed in Arabic or a language that one is able to understand. And that the person understands and believes that the ruqyah itself is not the cure but that Allah Subhana Wa’Tala has given the cure , the ruqyah is the appropriate means that Allah has provided.
2. Ruqyah Ash Shirkiyyah – this form of Ruqya is completely impermissible. It involves seeking the help of other than Allah eg calling on prophets, the dead, names of spirits, angels , pious believers etc. This is completely contradictory to tawheed and indeed is major shirk which removes one from the fold of Islam. Sadly there are raaqi who do perform this kind of ruqyah and you may not recognise it as they may speak in another language or use names and vocabulary that you are not familiar with , in order to get you to associate partners with Allah while you are unaware of what you are saying. This form of Ruqyah is not permitted whatsoever under Islamic law.