A recent experimental study was conducted in a pharmacology laboratory in Abidjan on the immunomodulatory activity of a plant remedy. The dose of cyclophosphamide used to depress the rats in the study at the beginning of the experiment did not give the expected results. The objective of this work was to determine the optimal dose of immunosuppressive cyclophosphamide in wistar rats raised in this laboratory. This was an experimental study conducted over eight (08) days. Groups (09) of animals received increasing doses of cyclophosphamide administered subcutaneously and intraperitoneally at the beginning of the experiment. Another group received 0.9% NaCl saline by gavage. The blood sample of each animal in this experiment was collected, and at the end of the study on EDTA tube to perform a blood count. Differences between animal groups were considered significant for a p value ? 5%. Cyclophosphamide 200 mg/Kg administered subcutaneously reduced leukocytes more effectively (p < 0.01) but caused necrosis at the injection site and several animal deaths. Intraperitoneal administration of 100 and 150 mg/Kg cyclophosphamide resulted in significant decreases in leukocytes (p < 0.05) with effects mainly on neutrophils and lymphocytes (p < 0.05) without impacting animal morbidity. The dose of 100 mg/Kg of cyclophosphamide administered intraperitoneally was shown to be the optimal immunosuppressive dose with a good dose-effectiveness ratio. It could be used for trials aiming to demonstrate an immunomodulatory effect of medicinal plants.

Keywords: Immunosuppressive; Cyclophosphamide; Wistar rat