All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger.
The treatment of magic is done by Ruqyah (Quranic recitations and supplication) and the like, and reciting the Quran on water and drinking it or bathing with it, and this is beneficial with the Will of Allaah.
If it is known that drinking water has an effect in invalidating that magic or that this water will be drunk because the Quran was recited on it, and the like, then there is nothing wrong with drinking too much of it, and this is not against the Sunnah because it is used as a medical treatment in this case. Seeking treatment is part of the Sunnah of the Prophet which he ordered us with and legislated for his nation.
Allaah knows best.