Pruritus pathophysiology

For more information on pruritus, see Chap. 48, Hemodialysis and Peritoneal Dialysis, authored by Edward F. Foote and Harold J. Manley, in Pharmacotherapy A Pathophysiologic Approach, seventh edition. 

Despite the well-known clinical coupling of dry skin and itch, studies to objectively compare the degree of skin hydration or measurements of the transepidermal water losses with severity of pruritus have provided conflicting results on this close association. This review will discuss the existing data, breakdown the pathophysiology of xerotic itch, and describe the role of moisturizers in alleviating both entities. 

A woman with chronic cholestasis and disabling pruritus had severe but transient opioid withdrawal-like reactions after oral naltrexone 12.5 mg and 2 mg (18). This observation suggests the hypothesis that increased central opioidergic tone is a component of the pathophysiology of cholestasis. 

Stander S, Steinhoff M Pathophysiology of pruritus in atopic dermatitis an overview. Exp Dermatol 2002 11 12-24. 

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