A psychiatrist uses hypnosis. Can a mentally ill person go to this psychiatrist for treatment under the condition that the mentally ill person would refuse the treatment by hypnosis when suggested by the psychiatrist?
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
We do not see any harm in going to the doctor whom you referred to in the question and be treated by him in a permissible manner. The fact that he treats some people by what is forbidden does not prevent from being treated by him in a permissible way.
The Jews in Al-Madeenah used to consume Riba and bribery (money), yet the Prophet did not refrain from dealing with them in what is permissible. Indeed, he used to trade with them and he died while his shield was mortgaged with one of them.
"A group of scholars thought that dealing with them (the Jews) is not permissible because their money is ill-gotten. However, the correct opinion is that it is permissible to deal with them despite them consuming Riba and transgressing what Allah has forbidden for them: there is clear-cut evidence confirming this in the Quran and the Sunnah." [End of quote]
Since the patient is mentally ill, as you mentioned, then one should take precautions not to leave him alone with the psychiatrist, rather the patient should be accompanied by someone who would see the method of treatment.
It is better for you to find other competent doctors (psychiatrists) who are not involved in what is forbidden and in doubtful matters, in order to be on the safe side.
Finally, since you write to us in Arabic sometimes, then we refer you to a Fatwa on the ruling on hypnosis in our Arabic section under number 101320, so please refer to it.
Also, for more benefit, please refer to Fatwa 323695 in our English site.
Allah knows best.
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