Phototoxic reaction to chlorpromazine as studied with the quantitative mouse tail technique.

A quantitative in vivo technique for the study of the phototoxic reaction to systemic chlorpromazine has been developed, based on the increasing tissue fluid content of the albino mouse tail. A maximum increase in tissue fluid of about 25% was registered 24 hours after starting the long-wave ultraviolet light exposure. The minimum phototoxic dose of chlorpromazine was 2.5 mg/kg.