Purpose: Increasing interest in carnosic acid (CA) is due to its pharmacological properties. The aim of this
study was to evaluate the acute and 30-day oral toxicity of CA.
Methods: The acute oral toxicity study in Kuming mice design followed the OECD-guidelines 423, and a
30-day chronic oral toxicity study in Wistar rats based on the enhanced OECD test guideline 407 were
performed.
Results: The oral lethal dose (LD50) for mice was 7100 mg/kg of body weight in the acute toxicity study.
The histopathological changes were observed in the heart, liver and kidney for the survival mice treated
with a single dose CA. For the sub chronic toxicity study, CA administered for 30 days produced slightly
reductions in the weight gain pattern, which did not reach the significant level when compared with the
control values. With respect to serum biochemistry test, decreased total serum protein levels, but conversely increased aspartate aminotransferase (AST) levels were detected in the high-dose and moder-
ate-dose groups. Histopathologically, light pathological changes were observed in the heart, liver, and
kidney of rats treated with the high-dose CA.
Conclusion: The present work suggests that a short-term oral administration of CA has a relatively low
toxicity profile.