Untrained or inexperienced therapists may prompt negative reactions in the use of aversion techniques that can make a person uncomfortable. An example would be causing a person to get nauseated when they see candy or smell cigarette smoke. This could be a problem.
Some hypnotherapists help patients go back in time in their lives to determine why they may be afraid or anxious about certain situations. The therapist may inadvertently plant false memories by not distinguishing a patient’s fantasies from realities. These are the instances when hypnosis can get dangerous.