Hypnosis for Medical cure?

Igros Moshe (YD II #29) Hypnosis is simply a natural phenomenon resulting from the influence on nerves and is not witchcraft. However I know that doctors generally do not utilize it. They do not rely that the person will be in a trance so that he can have an operation. Nevertheless if someone does this there is no reason to object since this is not witchcraft. 

Igros Moshe ( YD III #44) Question Is it permitted to cure through hypnotism? Answer I have discussed this with some people who know a little about this as well as Rav Henkin and we do not consider it as something prohibited since it is not witchcraft but is a natural phenomenon. Some people have the ability to influence people such as those with with weak nerves who don’t know what is happening. However there is a possible concern that the doctor might tell the person to transgress a Torah prohibition This would not be considered an unwitting sin since the person by his consent to be hypnotized brought this about. This would be comparable to a person going to sleep next to breakable items. If he breaks them while sleeping it is not considered an unwitting act. However if the doctor is not suspected of doing this such as a religious doctor or for some other reason, I don’t see that hypnosis is prohibited. Nevertheless it is an act of self degradation which has an aspect of prohibition as we see that someone who eats in the street is disqualified from being a witness. Thus even though it is not prohibited a person should not do it unless it is for medical purposes for which it is permitted to degrade oneself if needed even if there is no danger. .If there is mortal danger that removes prohibitions In cases were there will be no likely degradation it is possible to use.