Although myths about it abound, this form of therapy is often helpful.

Hypnosis is one of the oldest forms of psychotherapy in the Western world, and it may also be the most misunderstood. Although long associated with charlatans or performers, all true hypnosis is, by definition, self-hypnosis. In spite of the prevailing myth, nobody can be hypnotized against his or her will. Instead, hypnosis is generally induced by focusing attention on positive mental imagery.

A spate of papers on the topic have urged clinicians to remember that this therapy is an option when treating patients.

When to consider hypnosis

A number of hypnotic techniques exist, combining relaxation with imagery. People who undergo hypnosis may achieve a trancelike state, similar to what happens when they daydream or meditate. But hypnosis is actually a heightened state of concentration. The aim is to focus the mind to eliminate distractions and make someone more open to suggestions, such as those that promote the aims of treatment.

The American Medical Association approved hypnosis as a therapy in 1958, and the American Psychiatric Association followed in 1961. Since then, reviews have provided evidence about when this therapy is effective.

Pain relief. A meta-analysis published in 2000 concluded that hypnosis offered moderate to major relief for many types of pain. And a 2003 analysis found that hypnosis was at times more effective than other pain relief methods.

Hypnosis may be used as an adjunct to various types of sedation during surgery. A 1999 review concluded that hypnosis combined with conscious sedation might also reduce length of stay in the hospital by speeding recovery. A 2007 study found that women who were hypnotized before undergoing a breast biopsy or lumpectomy required less sedation during the procedure, and experienced less pain, nausea, and emotional distress afterward.

Studies also report that hypnosis can be effective for alleviating pain caused by chronic tension headaches and migraine headaches.

Anxiety. Hypnosis also helps to alleviate anxiety. It has been studied most as a treatment for anxiety related to surgery. Many studies have reported that hypnosis reduced anxiety levels and lowered blood pressure in patients before surgery, and enhanced recovery afterward by shortening hospital stays and reducing complications like nausea and vomiting.

In a 2006 study, for example, patients who underwent hypnosis received suggestions of well-being before surgery. Upon entering the operating room, they reported anxiety levels 56% lower than anxiety levels before hypnosis. Patients in a comparison group, who received the normal presurgical standard of care, reported a 47% increase in anxiety.

Where questions remain

For other conditions, the evidence about the effectiveness of hypnosis is mixed or insufficient.

Depression. One study involving 84 people with depression, who were randomly assigned to 16 weeks of treatment with either hypnosis or cognitive behavioral therapy (CBT), found that both groups improved with treatment. The hypnosis group made greater improvements than the CBT group when symptoms were rated on scales such as the Beck Depression Inventory and the Beck Anxiety Inventory, but the gains were small.

Eating disorders. An analysis found that many studies provided so few specifics that the hypnotic intervention could not be replicated nor evaluated. Further research in this area is needed.

Schizophrenia. Some researchers question whether people with this disease are capable of being hypnotized, while others worry that hypnosis might trigger a psychotic episode. Although case reports suggested that hypnosis may help some patients improve concentration, attention, and cognitive function, a comprehensive review concluded that the available studies were too small, poorly designed, and outdated to provide any guidance.

Smoking cessation. Some studies suggested that hypnosis might help people stop smoking by reducing cravings, bolstering willpower, or increasing focus on healthier choices. But a comprehensive review found that most evidence to date consisted of case reports or poorly designed studies, and it concluded that hypnosis is no better than other interventions — or even no treatment at all — on six-month quit rates.

Finding a qualified hypnotherapist

Many states do not regulate hypnotherapy. To find a qualified therapist, ask if the person is licensed (not just certified) to practice. Or check for membership in the American Society of Clinical Hypnosis or the Society for Clinical and Experimental Hypnosis, two nationally recognized organizations for licensed professionals in this field.

Alladin A, et al. “Cognitive Hypnotherapy for Depression: An Empirical Investigation,” International Journal of Clinical and Experimental Hypnosis (April 2007), Vol. 55, No. 2, pp. 147–66.

Barabasz M. “Efficacy of Hypnotherapy in the Treatment of Eating Disorders,” International Journal of Clinical and Experimental Hypnosis (July 2007), Vol. 55, No. 3, pp. 318–35.

Spiegel D. “The Mind Prepared: Hypnosis in Surgery,” Journal of the National Cancer Institute (Sept. 5, 2007), Vol. 99, No. 17, pp. 1280–1.

For more references, please see www.health.harvard.edu/mentalextra.

Last Updated: 03/08