IM in medical terms mainly refers to intramuscular injection, which is done by means of a syringe, injecting the drug into the muscle tissue, thus providing a therapeutic effect. It is mainly used for patients who are not suitable or cannot use intravenous infusion, and require faster therapeutic effect than subcutaneous injection. Generally, intramuscular injections are mainly chosen to be performed in areas with abundant muscles and relatively distant from important locations such as large blood vessels and nerves, such as the gluteus maximus, gluteus medius, gluteus minimus, lateral femoris, and upper arm deltoid. Although the risk of routine intramuscular injections is not significant, attention should be paid to the following aspects: 1. Injection sites: For example, patients with chronic viral infections, tuberculosis and other diseases of long duration should alternate injection sites in order to avoid the appearance of hard nodules on the skin, as they may need long-term intramuscular injections. If hard nodules have appeared at the injection site, physical therapy such as infrared light and microwave can be used to relieve them; 2, sterile cotton swab pressure: after intramuscular injection, in order to relieve bleeding at the injection site, patients can use sterile cotton swabs to press for 2-3 minutes; 3, avoid fasting injection: when performing intramuscular injection, as fasting may induce nausea, vomiting and other gastrointestinal reactions, so patients need to moderate the amount of intake of food; 4. Adverse reactions: If the patient has symptoms such as dyspnea, facial redness and swelling, skin itching, etc., serious cases may have shock reactions. At this time, considering that an allergic reaction may occur during the intramuscular injection, it is necessary to seek medical attention promptly and use loratadine tablets etc. to relieve discomfort under the guidance of a doctor, and to administer oxygen therapy if necessary. In addition, intramuscular injections in the gluteus maximus area are not recommended for infants and children under 2 years of age, mainly because of the risk of injury to the sciatic nerve and the possibility of certain adverse effects on the muscle development of infants and children. Infants and toddlers can choose to have injections in the gluteus medius and gluteus minimus before they achieve independent walking due to poor muscle development in the glutes.