Potentiation of haloperidol-induced catalepsy by ascorbic acid in rats and nonhuman primates

Ascorbic acid was examined for potentiative effects on the catalepsy induced by haloperidol in rats and squirrel monkeys. In both animal species pretreatment with ascorbic acid (1000 mg/kg) markedly potentiated catalepsy induced by haloperidol. It is suggested that vitamin binds to, and inactivates, some brain dopamine receptors and in so doing potentiates an otherwise minimally cataleptogenic dose of haloperidol.