Embryo-fetal developmental toxicity of carbamazepine administered orally in wistar rat

Carbamazepine is an anticonvulsant medication commonly used to treat epilepsy and other neurological disorders. The purpose of this study was to assess the impact of carbamazepine on prenatal development, including maternal-fetal, external, visceral, and skeletal toxicity. Additionally, the study aimed to investigate the effects of orally administered Carbamazepine at a lower dose range in Wistar rats. Pregnant female rats were randomly distributed into control (G1) group administered with distilled water orally (n=8), low dose (G2) group administered at 25 mg/kg, intermediate dose (G3) group at 50 mg/kg, and high dose (G4) group at 100 mg/kg through oral gavage from gestation day (GD) 5-19. Pregnant female rats were scheduled to necropsy on gestation day (GD) 20. During the evaluation, the uterus was observed for number of live or viable fetuses, dead fetuses, early resorptions, late resorptions, number of corpora lutea and the sex ratio (m/f) per litter. Further, fetuses were subjected to materno-fetal examination which included observation for placenta, amniotic fluid, and umbilical cord followed by external evaluation. Additionally, half of the fetuses were subjected to visceral, craniofacial evaluation and other half of the fetuses were subjected to skeletal evaluation by double staining method using Alcian Blue for cartilages and Alizarin Red S for bones. It was observed that there was a significant decrease in the rate of pregnancy in the intermediate dose (G3) group and in high dose (G4) group when compared with the control group. Moreover, treatment with the Carbamazepine caused significant increase in fetal malformations such as dilation of lateral and third ventricle in brain, in intermediate dose (G3) group and high dose (G4) group when compared with the control (G1) group, dilation of ureters in high dose (G4) group. Fetal skeletal malformations like bent and nodulated ribs were also observed in intermediate dose (G3) group. Existing research substantially supports the claim that carbamazepine can cause teratogenic effects and prenatal development toxicity even at a lower dose range.