Healthy personal routine and habits can affect negativity quite a bit, sometimes, and for pagans, that often means the right incense. The younger the patient, the more important it becomes to use "positive displacement" with regard to dark parasitic or predatory entities. If you can find a real clairvoyant who can actually see beings that don't belong hanging around the aura of a human being, especially a young one, then it shouldn't be difficult to find a witch or witch doctor who knows what prayers and potions might be needed to get rid of the nasty hangers on, if that is the situation. In the case of neurological disorders with a physical etiology, negative entities are very difficult to effectively banish. So, it might be best to find out what the medical and psychiatric experts have to say about the patient before proceeding to more arcane measures. Sometimes, pesticides in the drinking water or similar phenomena can erode a human's well being. In such a case, if you undertake some magical remedy like a mantra that evokes strong intervention, if it works well, it could even lead to the exposure of deleterious physical influences. I once had a young roommate who was pestered by evil spirits, and my then priest of Osiris gave me some of his kyphi. I burned some, and it banished the distress immediately and miraculously. But, my pal's lifestyle and outlook were not very wholesome, and the effects were not long lasting, just dramatic enough to let me know that real demons were at work, and that our paths would soon diverge because of karma. You can't force a person long term to be free of negativity if it isn't the choice of the individual. Those demons were actually enabling my friend to choose the dark path to which he was deeply attracted, and putting me on notice that there was only so much I could do with regard to Jedi type mystic influence.