Short term toxicity study in rats dosed with peppermint oil.

Peppermint oil was given p.o. to groups of 10 male and 10 female rats at dosage levels of 0, 10, 40 and 100 mg/kg bw/day respectively for 28 days. Histopathological changes in the white matter of the cerebellum especially were seen at dose levels of 40 and 100 mg/kg bw/day and consisted of cyst-like spaces scattered in the white matter. There were no obvious signs of clinical symptoms due to the encephalopathy.