Rabbit as a model for chlorpromazine-induced hyperpigmentation of the skin

Hyperpigmentation of exposed skin areas, comparable to that seen in less than 1 per cent of patients chronically dosed with chlorpromazine after intensive long-term therapy, has been produced in sixteen out of sixteen chronically dosed pigmented rabbits, receiving between 20-30 mg/kg per day. Thirty-min u.v. irradiation of a clipped or shaved area produced clear-cut hyperpigmentation of naturally pigmented skin areas in about 4 weeks. The characteristic occurrence of granular pigment in the dermis which is normally free of pigment was also observed. Hyperpigmented rabbits did not develop any concomitant ocular pathology, as seen in some patients on long-term, high-dosage chlorpromazine therapy.