In the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) [4] recurrent SP, most commonly affecting the face, arms and hands, that results in skin lesions and significant distress and impairment in the occupational, social or other areas of functioning, is classified as Skin-Picking Disorder (SPD) or Excoriation Disorder, under the section on Obsessive- Compulsive and Related Disorders (OCRD) [4]. SPD [4] often begins in adolescence in association with the onset of acne and picking of the acne lesion (acne excoriée), however the picking may involve clinically healthy skin, minor skin irregularities, other pimples, calluses or scabs resulting from self-excoriation [4]. SPD can occur in all age groups, and may have first onset in a previously active person who loses mobility e.g., due to accident or illness [32]. The skin picking may be accompanied by a range of rituals or behaviors involving the skin or scabs, and some individuals engage in skin picking that is more focused, with preceding tension and subsequent relief, features that are consistent with obsessive-compulsive symptoms [4]. Some individuals may engage in more automatic skin picking with the picking seeming to occur without full awareness and without preceding tension, symptoms that are consistent with dissociation [5]. The DSM-5 mentions that many patients have a mix of both (i.e., obsessive-compulsive and dissociative) behavioral styles. In patients where SP occurs without preceding tension or full awareness, there typically tends to be much higher levels of stress and dissociation, and such patients require stabilization and assessment for suicide risk [5]. Stressful life events are known to be associated with the onset of obsessive-compulsive symptoms [33]. Psychological trauma and traumatic stress are well recognized precursors of dissociation [34]. Stress may therefore precede and be the result of SPD.

SP involving acne or other skin lesions, may be a feature of excessive grooming in Body Dysmorphic Disorder (BDD) (DSM-5) [4], also classified under OCRD, where the patient is preoccupied with a perceived defect in their physical appearance. The compulsive SP which is intended to improve the perceived defects in the skin can cause skin damage and infections [4]. The individual feels driven to perform the SP, which may not be pleasurable and may increase the anxiety and dysphoria, and cause clinically significant distress or impairment in social, occupational and other areas of functioning [4].

SP may be encountered in a wide range of other psychiatric disorders where stress can play a role in the onset or exacerbation of the disorder [4].

Psychological stress and psychiatric factors are important in one-third of dermatology patients [36]. A large number of dermatologic disorders that are exacerbated by psychological stress have an immune basis and are associated with pruritus e.g. psoriasis, atopic dermatitis and chronic idiopathic urticaria. Stress can precipitate SP in these patients. A blunted HPA-axis cortisol response and heightened sympathetic response to stressors have been observed in psoriasis [37–39], factors that can decrease the threshold for pruritus perception and predispose the patient to SP.