Study of the effects of certain drugs on experimental porphyria in rats.

The effect of ethanol, phenobarbitone, griseofulvin or chloroquine on 3,4-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced porphyria in rats has been studied in experiments lasting up to 40 days. Ethanol, phenobarbitone or griseofulvin given later, in addition to DDC, resulted in a clearly greater porphyrin excretion and liver porphyrin concentration than with DDC alone. Chloroquine at first increased, then decreased porphyrin excretion and liver porphyrin was lowered. No drug without DDC was porphyrogenic.