Experimental chlorpromazine cataracts.

Abstract

Chronic ingestion of large doses of chlorpromazine (CPZ) by human beings has been associated with the production of corneal and lens opacities, and less frequently with chorioretinal pigmentation, and a peculiar purplish coloration of exposed skin and conjunctiva. When guinea pigs were fed large doses of CPZ and exposed to ultraviolet light, lens opacities were consistently produced that resemble those in human patients on chronic high doses of CPZ. They developed in albino and pigmented animals. A progressive increasing deposition of CPZ with increased treatment was demonstrated in the lens and other tissues of treated guinea pigs, and occurred in albino and pigmented animals. The respiratory metabolism of lens epithelium of CPZ-treated animals teas reduced by a statistically significant amount in this study, xohen compared to control values. Sodium succinate was shown to stimidate respiration in CPZtreated, but not control, lens epithelium (both exposed to glucose substrate). It appears that CPZ alters respiratory mechanisms by effecting a metabolic block at some site preceding succinate. On the basis of this study, the CPZ cataract has no apparent relation to melaniti. It may represent foci of denatured protein resulting from the interaction of light with the drug, a photosensitizing agent, and lens protein, or possibly deposits of drug within the lens.