Lichen simplex chronicus on the scalp, also known as trichoteiromania, can be difficult to manage, as the therapeutic options are limited to topical or intralesional glucocorticoids. We describe a patient with trichoteiromania, presenting three lichenified pruriginous plaques on different regions of the scalp, associated with fracture and loss of hair shafts. Prior treatment with potent topical glucocorticoids was ineffective. However, treatment with oral N-acetylcysteine (NAC) 1,200 mg/day resulted in complete hair regrowth within 16 weeks. NAC is a safe drug with a good tolerance profile that could be a therapeutic option for patients with trichoteiromania. The potential of NAC has not been completely elucidated, thus more studies will be necessary to confirm its efficacy in the long term for some psychodermatological conditions.