History: Prurigo nodularis is a chronic dermatitis characterized by discrete, raised, firm hyperkeratotic papulonodules, usually from 5 to 12 mm in diameter but occasionally larger. They occur chiefly on the extensor surfaces of the extremities and are intensely pruritic. The disease usually begins in middle age and women are more frequently affected than men. The cause remains unknown but local trauma, insect bites, atopic background, and metabolic or systemic diseases have been implicated as predisposing factors in some cases.