pruritic

Pruritic is an adjective used to describe something that causes pruritus, the sensation of itch. The term derives from Latin pruritus (itch) and the verb prurire (to itch). Pruritus can accompany many medical conditions or occur on its own. When itching persists for more than six weeks, it is considered chronic and warrants evaluation to identify an underlying cause, which may be dermatologic, systemic, infectious, or drug-related. It may be localized, such as an itchy patch of dermatitis, or generalized, without a clear rash.

Common causes include inflammatory skin diseases (eczema, contact dermatitis, psoriasis), fungal or bacterial infections, infestations such as scabies, and allergic reactions. Systemic causes include chronic kidney disease, cholestatic or liver disease, thyroid disorders, iron deficiency, malignancy, and certain medications. Pregnancy and environmental irritants can also contribute. In many cases, pruritus results from multiple factors.

Pathophysiology involves itch-sensing nerve fibers and central nervous system processing. Histamine is a mediator in some cases, but many itchy conditions are non-histaminergic and may respond poorly to antihistamines.

Management focuses on treating the underlying cause when possible, and relieving symptoms with moisturizers, topical corticosteroids or calcineurin inhibitors for dermatitis, and non-sedating or sedating antihistamines as needed. For neuropathic or chronic pruritus, agents such as gabapentinoids or certain antidepressants may be used. Severe refractory cases may benefit from phototherapy or systemic therapies.

A clinician should assess chronic pruritus to exclude serious illness and tailor treatment to the individual.