Rectal medications are generally not very harmful when given correctly; improper handling may cause rectal injury and pain, bleeding, and decreased bowel reflexes. Rectal drug delivery is the method of delivering drugs through the anus to the rectum, sigmoid colon, or higher. Absorbed through the rectal mucosa, the drug can enter the body’s circulation, thus achieving the purpose of treating local or systemic diseases. In general, if the operation is correct and used in accordance with medical advice, it will not lead to serious harm. Usually the harm of rectal drug administration is mainly caused by improper clinical operation. For example, if a patient is not careful during rectal administration, the stiffer catheter may puncture the rectal mucosa, resulting in rectal injury and pain. In addition, repeated enemas may also lead to infection of the rectal mucosa, causing bleeding, weakened bowel reflexes and other damage. It is recommended that patients need to use the medication under the guidance of a medical professional, and should not use the medication privately to avoid adverse consequences.