Background: Camphor is an herbal medicine that has been reported to have various physiological effects. It has been reported to affect the respiratory system, circulatory system, skin, reproductive system, liver, and kidneys.

Objectives: This study is to determine the effect of orally administered Cinnamomum camphora on the histoarchitecture, antioxidant defense and renal function tests using Wistar rats as the experimental models.

Methods: A total of 20 Wistar rats were used and randomly divided into 4 groups of 5 animals, group A served as Control, received 1 ml of Distilled water, group B served as the Vehicle, received 1 ml of olive oil, Groups C and D received 200 and 400 mg/kg of Camphora (dissolved in olive oil) respectively for 4 weeks. Blood samples were collected for kidney function tests (urea, creatinine and albumin levels) and kidneys were harvested for histological (H&E) and oxidative stress analyses.

Results: There was a significant increase in urea, creatinine and albumin levels in groups B, C and D when compared to the control. There was a significant decrease in SOD and CAT when treatment groups were compared to control, however, significant increase was noted when treatment groups were compared to control in MDA levels. Histopathological studies showed moderate vascular congestion in the treatment group.

Conclusion: In conclusion, this study revealed that camphora had toxic effects on the anti-oxidative defense, renal functions and kidney histomorphology.