The common complications of intravenous infusion are mainly the following: First, fever. The presence of heat sources within the fluid causes the body to react with fever, and in severe cases the patient may even go into shock. Second, allergy, allergies are very dangerous, sometimes leading to laryngeal edema and even sudden death. Third, phlebitis, phlebitis is a superficial venous thrombosis caused by the application of many drugs that can stimulate the lining of blood vessels. Fourth, hematoma, often due to failure to press the blood vessel in time to stop bleeding during infusion, resulting in blood leakage and formation of hematoma under the skin. Fifth, fluid leaks out into the subcutis, leading to skin irritation or necrosis.