Trichotillomania is a disorder characterized by an overwhelming urge to repeatedly pull out one's own hair, resulting in hair loss (alopecia). It is classified under the obsessive-compulsive and related disorders category. Trichotillomania results in highly variable patterns of hair loss. The scalp is the most common area of hair pulling, followed by the eyebrows, eyelashes, pubic and perirectal areas, axillae, limbs, torso, and face. The resulting alopecia can range from thin unnoticeable areas of hair loss to total baldness. Some people chew or swallow the hair they pull out (trichophagy), which can result in gastrointestinal problems or develop a trichobezoar (hairball in the intestines or stomach). In many cases, people with this disorder feel extreme tension when they feel an impulse, followed by relief, gratification or pleasure afterwards.

The disorder may be mild and manageable, or severe and debilitating. The cause is unknown, though both environmental and genetic causes have been suspected. Treatment may involve cognitive behavior therapy, such as habit reversal training (learning to substitute the hair-pulling behavior) and/or drug therapy, but these are not always effective.

Behavioral treatment seems to be the most powerful treatment for trichotillomania. Parental involvement is important and should include enough support so that affected children grow well intellectually, physically, and socially. Shaving or clipping hair close to the scalp may be helpful to stop the behavior.

Professional cognitive behavior therapy (CBT) is recommended if initial approaches are unsuccessful. CBT typically involves self monitoring (keeping records of the behavior); habit-reversal training; and stimulus control (organizing the environment). CBT is typically effective in highly motivated and compliant patients. The success of therapy may depend on firm understanding of the illness and the cooperation of the family members to help the affected individual comply with treatment. Several courses of CBT may be needed.

No medication has been approved for the treatment of trichotillomania, and medications used have not been consistently effective. Selective serotonin reuptake inhibitors have been utilized but responses to treatment have not been consistent. Fortunately, several recent studies regarding drug therapy for trichotillomania show promise. While drug therapy alone is currently generally not effective, combination therapy and other treatments may be helpful.