Rabies immunoglobulin refers to the immune antibody to rabies. After a person is bitten by an animal such as a cat or dog, rabies immunoglobulin needs to be injected promptly and within 24 hours. This immunoglobulin can neutralize the virus in the body, thus achieving the removal of rabies virus and blocking the possibility of rabies virus infection to the body. If a person has not received rabies vaccine within three months, after being bitten, a combined rabies vaccination is required to prevent the patient from contracting rabies to the greatest extent possible. If a patient is not vaccinated within 24 hours, there is a high probability that he or she will be infected with rabies, and the mortality rate is 100 percent once the disease develops. Once bitten, he or she should go to the hospital promptly to take appropriate treatment measures to avoid serious consequences.