According to Shailesh Jain, MD, MPH, ABDA: "Patients with psychogenic itch predominantly are female, with average age of onset between 30 and 45 years.1 Psychiatric disorders associated with psychogenic itch include depression, obsessive compulsive disorder, anxiety, somatoform disorders, mania, psychosis, and substance abuse.2 Body dysmorphic disorder, trichotillomania, kleptomania, and borderline personality disorder may be comorbid in patients with psychogenic itch" Obviously this is a general symptom that goes with many psychological problems.
Things like skin picking and cutting cause the production of endogenous opioids, so they become addictions. Both deficient and excessive μ opioid receptor signalling results in social behaviour impairments.
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