Psychogenic pruritus, (psychogenic itch) or functional itch disorder is pruritus not associated with a dermatologic or systemic cause.
More often than not, it is attributed to a psychiatric cause.
Psychogenic pruritus is not the same as neuropathic itch.
It is typically considered a diagnosis of exclusion.
Psychogenic pruritus typically appears as itching on the face and on the extensor surfaces of the body, including the back side of the arms, the abdomen, the side of the legs and the upper back and shoulders.
These areas are more frequent because they can be reached by the hand.
It is important to rule out medical, dermatologic and neuropathic causes prior to diagnosis.
Evaluation:
History, laboratory for CBC, ESR, liver, renal and thyroid panel as abnormalities with any can contribute to pruritus.
Pruritus can be seen with hepatic and renal disease such as cholestasis, alcoholic liver disease, primary biliary cholangitis, hepatitis B and C, and chronic kidney disease.
Drug and alcohol use can contribute to pruritus.
Cocaine and amphetamine use may experience pruritus due to feelings of abnormal cutaneous sensations.
Functional itch disorder is the best phrase to describe this condition.
Diagnosis: three required criteria and three of seven optional criteria.
3 Required criteria:
Localized or generalized pruritus without a primary skin lesion
Chronic pruritus, characterized as being greater than 6 weeks
There is no somatic cause present
7 Optional criteria (need 3 to diagnose)
A chronological relationship of pruritus with one or several life events that can have psychological consequences
Changes during the nighttime
More present during rest or inaction
There is a coupled psychological disorder
Pruritus that could be improved with pyschotropic drugs
Pruritus that could be improved by psychotherapies
Treatment: most common options are psychotherapy and medicines geared toward psychiatric conditions.
Stress reduction and relaxation techniques have also been shown to be helpful for alleviating this condition.
Having a strong physician-patient association can also lead to the improvement of symptoms.
It is often managed with drugs including H1-antihistamines, tricyclic antidepressants, tetracyclic antidepressants, selective serotonin reuptake inhibitors, antipsychotics, or benzodiazepines.
Menthol and cool compresses can also relieve the patient of their itch.
It is also common for psychologic conditions such as obsessive-compulsive disorder, depression, anxiety, bipolar and psychosis to present with pruritus.
The incidence is not known. However,
It is more common in females of the age range of 30-45 years.