Efficacy of gabapentin in the management of pruritus of unknown origin.

Generalized pruritus is a distressing symptom that can occur in several dermatologic and systemic disorders. Generalized pruritus of unknown origin is that which affects patients without any underlying dermatologic or systemic disorder and is unassociated with rash. It most commonly occurs in older patients and persists for long periods, from months to years. In many cases, the itching may be due to reduced water content of the skin, without overt dryness. Failure of the normal processing of the itching sensation along the course of central and peripheral sensory pathways may also play a role.