Many people have nervous habits such as chewing on fingernails, moving feet or hands, or repeated hair pulling. Hair pulling that leads to noticeable hair loss is called trichotillomania. Trichotillomania can cause a lot of distress. Sites of hair pulling may include the scalp, eyebrows, eyelashes, or even pubic hair. Pulling may occur frequently for brief periods or during longer episodes that occur less often. Stressful situations often increase hair-pulling behavior, and people say that they feel tense immediately before hair pulling. Usually, hair pulling does not occur when other people are around (except close family members). Sometimes individuals avoid social situations so they can hide the behavior. Hair pulling can occur in both children and adults. About 1% to 2% of college students have engaged in this behavior. Examining the hair root, twirling the hair off, pulling strands of hair between the teeth, and eating hairs are other behaviors that may occur.

Habit reversal and control techniques are treatments that are useful for trichotillomania. While other approaches may be helpful for treatment of trichotillomania, they have not been evaluated scientifically in the same way as the treatments listed here.