Trichotillomania (hair pulling) is a compulsion to pull out one's own hair, leading to alopecia. It may serve as a method of emotional regulation wherein the stimulus helps alleviate stress or other negative emotions. It may vary from a mild habit to an impulse-control disorder. It is more common in females and usually starts in childhood or adolescence.

Individuals may pluck hair from any site.

If hairs are swallowed they can lead to trichobezoar in the stomach and other portions of the gastrointestinal tract that can present as symptomatic.