The side effects of immunosuppressants can be divided into several categories. One of the more clinically used and common types of immunosuppressants is hormones, the full name of which is glucocorticoids. These hormones are widely used in the clinic, and even in some places, drug resistance problems have emerged, and adverse reactions should be taken seriously. First of all, it can cause water and electrolyte disorders, and in addition, it can cause changes in body shape such as full moon face and buffalo back, which are unacceptable for girls. There is another condition that should be taken very seriously in children, which may affect normal growth and development. For all patients, the biggest problem with immunosuppressants is that while suppressing immunity, they can lead to infections, with an increased likelihood of viral, bacterial and other infections, and furthermore may cause tumorigenesis, which requires long-term observation. In conclusion, immunosuppressant use needs to be continued under the clear diagnosis of a doctor and under the supervision of a pharmacist in order to achieve the best efficacy and avoid adverse effects.