A toxicity study of simultaneous administration of Tamoxifen® and Diazepam® to female Wistar rats

Tamoxifen (TAM) is used in the treatment of breast cancer and decreases the incidence of breast cancer when given to healthy women for different therapeutic purposes. This expansion of its use calls for further studies of its own potential side effects and those in combination with other prescription drugs. Diazepam (DP) is one such drug normally administered to patients who are under cancer treatment and those who suffer from insomnia. The present study examines the effect of individual and simultaneous administration of TAM and DP at therapeutic dose level of 0.8 mg/Kg/day of TAM and 0.3 mg/Kg/day of DP to normal female Wistar rats for a period of 12 weeks. The drugs were administered orally by mixing it in pellet made by wheat dough. There was no significant change in the terminal body weight and liver weights of animals. The ovary weights in TAM + DP treated animals were significantly decreased. The serum succinate dehydrogenase (SDH) levels were significantly lower in TAM, DP and TAM + DP treated rats and comparatively were lowest in TAM and TAM + DP treated animal groups. Serum glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT), acid and alkaline phosphatase (ACP & ALP) levels were significantly higher in the three treated groups, but comparatively lower in TAM + DP treated animals when compared to TAM or DP alone treated rats. There was marked increase in liver triglyceride and cholesterol levels in the three treated groups but remarkable decrease in liver glycogen. Total serum cholesterol levels were significantly high in DP and TAM + DP treated rats and total serum triglyceride levels were significantly high only in TAM treated rats. As a whole it can be concluded that DP does not enhance TAM toxicity on simultaneous administration, but on its own when administered individually brings about perturbation in lipid storage and metabolism.