Heparin injection may affect liver function. Heparin is metabolized through the hepatic and renal pathways, and a longer duration and higher dose of heparin will easily aggravate the burden on the patient’s hepatic and renal functions, which may lead to pharmacological injury of the liver, and have a certain effect on the normal function of the hepatic and renal tissues. Heparin injection affects liver function, and the dosage of heparin needs to be adjusted according to the degree of injury. For mild injury, it is necessary to follow the doctor’s instructions to reduce the dose. For severe injury, heparin injections should be stopped. Heparin injection will produce certain side effects, in addition to affecting liver function, but also prone to cause spontaneous bleeding, occasionally severe allergic reactions and other conditions. Therefore, heparin injections must be taken under the guidance of a medical professional.