Cyclosporine A (CyA) is a lipophilic cyclic undecapeptide originally derived from the filamentous fungus Tolypocladium inflatum. CyA has been used as a potent immunosuppressive agent for the treatment of autoimmune diseases and a number of organ transplantations, such as kidney, liver, heart, and bone marrow, resulting in a significant improvement in clinical outcome. This study involved 30 renal transplanted patients whom received Cyclosporine A as an immunosuppressant after transplantation in order to reduce the receiver’s immune response against the donor’s tissue or graft rejection. Demographic patterns and total white blood cells and other serum parameters were evaluated in order to determine the effect of CsA within specific therapeutic regimen. Total WBC was significantly reduced in patients, Urea and creatinine were increased remarkably. Serum GPT, K⁺ and Ca+ were also significantly changed. Results showed that CsA might has a potential impact on decreasing the WBC counts and increasing the triglyceride, cholesterol and blood glucose and alters the liver function. The side effects of the drug was considered as a risk for hyperlipidemia and alters the liver enzymes activity.