How often to inject gammaglobulin needs to be taken at different intervals according to different diseases such as within 6 days for prevention of urticaria, within 5 days for hepatitis and once a month, and once every 5 weeks for poliomyelitis. 1. If it is for the prevention of urticaria and you have not been vaccinated against urticaria, you need to inject gammaglobulin within 6 days after close contact with a child suffering from urticaria, which is a more effective way of prevention. 2. If it is used for the prevention of hepatitis A, hepatitis B and other diseases, it is usually injected within 5 days after the history of contact, and thereafter it needs to be injected every 1 month to consolidate the preventive effect. 3. If the vaccine is used to prevent poliomyelitis, it is usually injected every 5 weeks to achieve the preventive effect. However, the specific injection method may change according to individual conditions and should be determined after consulting with a doctor. 4. Generally, there are no adverse reactions, mainly mild adverse reactions such as local swelling and pain; people with a history of severe allergy or IgA antibody allergy are prohibited from vaccination.