Olanzapine therapy for subacute prurigo

2020 guidelines for the diagnosis and treatment of prurigo

Prurigo is a treatment-resistant skin disease characterized by multiple isolated papules/nodules that cause severe itch. Prurigo papules/nodules occur either as primary lesions or as secondary lesions due to persistent scratching. The fundamental concepts and classifications of prurigo have not been sufficiently established, and considerable confusion remains regarding this topic. Clinical guidelines for chronic prurigo in Japan were published in 2012 in an attempt to reduce confusion regarding the concepts of prurigo and to standardize laboratory tests and treatments. However, the diagnostic terms for prurigo and associated concepts have changed over time, and new forms of treatment are under development. We have, thus, updated and revised the guidelines to classify prurigo based on clinical forms and causes, and disease name classifications based on the clinical form have been further simplified, such as prurigo nodularis, prurigo chronica multiformis, and prurigo (not otherwise specified). Expressions for acute, subacute, and chronic forms are not used. These guidelines outline the current concepts and specify treatments for prurigo.

Can we use psychoactive drugs to treat pruritus?

Pruritus is a frequent complaint both in dermatology and general medicine. This burdensome symptom has a complex and multifactorial pathogenesis, with the key involvement of central nervous system in its development. Psychoactive drugs (psychopharmaceuticals) encompass several therapeutic groups utilized mainly in psychiatry. However, these drugs are occasionally used in dermatological practice and may contribute to alleviation of pruritus in a variety of cutaneous and extracutaneous disorders. This review article summarizes the role of H1-antihistamines, antidepressants, antipsychotics and antiepileptics in managing pruritus.

Psychogenic Pruritus and Its Management

Chronic itching can be frustrating for patients and providers, and patients are not always willing to accept that their psychiatric health has an impact on their skin. Psychogenic pruritus is defined as itch not related to dermatologic or systemic causes. When a patient presents with pruritus, regardless of the presumed cause, the standard work-up should include a thorough history, dermatologic examination, and laboratory examinations or biopsies as needed. If no medical source is found, the provider must work in partnership with the patient to explore other causes and that may include acknowledging and treating underlying psychiatric conditions.

Psychiatric medications for the treatment of pruritus

OBJECTIVES

To review the use of psychiatric medications in the treatment of pruritus.

METHODS

A literature review was conducted using the key words pruritus, psychiatric, and treatment.

RESULTS

Three categories of pruritus are described: dermatologic, systemic, and psychogenic. Peripheral and central nervous system mechanisms of pruritus are reviewed. Conventional dermatologic treatments for pruritus are contrasted with some of the common psychopharmacologic treatment modalities that include anxiolytic, antidepressant, and antipsychotic agents. A treatment algorithm is offered to help guide the treatment of patients with pruritus.

CONCLUSIONS

Psychiatric medications have been used successfully in the treatment of pruritus that is associated with both psychocutaneous and systemic disorders, which are resistant to conventional treatment.

Psychocutaneous syndromes: a call for revised nomenclature

We propose abandoning three outdated, pejorative diagnostic terms: 'trichotillomania', 'delusions of parasitosis', and 'neurotic excoriation'. These insensitive terms are offensive to patients and become a barrier to treatment. We suggest the following alternative patient-centred nomenclature: 'neuromechanical alopecia', 'pseudoparasitic dysaesthesia', and (simply) 'excoriation'. We briefly review clinical and historical aspects of these disorders.