Immunosuppressive drugs are a specialized category of pharmaceuticals that inhibit the immune system's activity. Their primary application is in the prevention of organ transplant rejection. These drugs are essential in ensuring the success of organ transplantation, extending and improving the lives of recipients. Immunosuppressive regimens are carefully tailored to each patient, balancing the need to suppress the immune response against the risk of leaving the patient vulnerable to infections. Immunosuppressive drugs have made transplantation a routine and life-saving medical procedure.