Hypnosis or deep relaxation can sometimes exacerbate psychological problems—for example, by retraumatizing those with post-traumatic disorders or by inducing “false memories” in psychologically susceptible individuals. Evidence, although inconclusive, has raised concerns that the dissociation necessary to participate in relaxation or hypnosis can lead to the manifestation of the symptoms of psychosis. Only appropriately trained and experienced practitioners should undertake hypnosis. Its use should be avoided in patients with borderline personality disorder, dissociative disorders, or with patients who have histories of profound abuse. Competent hypnotherapists are skilled in recognizing and referring patients with these conditions.
However, Freud gradually abandoned hypnotism in favour of psychoanalysis, emphasizing free association and interpretation of the unconscious. Struggling with the great expense of time that psychoanalysis required, Freud later suggested that it might be combined with hypnotic suggestion to hasten the outcome of treatment, but that this would probably weaken the outcome: "It is very probable, too, that the application of our therapy to numbers will compel us to alloy the pure gold of analysis plentifully with the copper of direct [hypnotic] suggestion."
Since hypnotherapy is an adjunct form of therapy, used along with other forms of psychological or medical treatment, there are many applications. Hypnotherapy can be used to treat anxiety, phobias, substance abuse including tobacco, sexual dysfunction, undesirable spontaneous behaviors, and bad habits. It can be used to help improve sleep, learning disorders, communication, and relationship issues. Hypnotherapy can aid in pain management and help resolve medical conditions such as digestive disorders, skin issues, and gastrointestinal side effects of pregnancy and chemotherapy. It can also be used by dentists to help patients control their fears or to treat teeth grinding and other oral conditions.