Avoiding serious adverse reactions such as nephrotoxicity due to overdose is one of the important clinical implications of cyclosporine therapeutic drug concentration monitoring (TDM). Cyclosporine is a potent immunosuppressant widely used to prevent rejection after organ transplantation. However, due to its narrow therapeutic window, improper dose control may lead to serious adverse reactions, especially nephrotoxicity. By implementing TDM, physicians are able to accurately monitor the concentration of cyclosporine in a patient's blood to ensure that it is maintained within a safe and effective therapeutic range. This not only helps to avoid nephrotoxicity due to overdose, but also reduces other potentially serious adverse reactions, such as neurotoxicity and digestive reactions. In addition, with TDM, physicians can more effectively manage patients' immunosuppressive therapy, reduce fluctuations in drug dosage, and improve the safety and efficacy of treatment. Therefore, cyclosporine TDM plays a crucial role in reducing drug dose-related adverse reactions, and it provides a safer and more reliable treatment option for patients, ensuring treatment precision and patient safety.