Why does a child's injection site itch after receiving the hepatitis B vaccine, and what should be done?

Generally, itching at the injection site after a child receives the hepatitis B vaccine may be caused by drug irritation, adverse reactions to the vaccine, or infection. Appropriate treatment should be based on the specific situation. Details are as follows:

1. Drug irritation

If a child has a relatively weak constitution, the medication may irritate the skin and cause itching at the injection site. These symptoms usually disappear quickly and do not require special treatment.

2. Adverse reaction to the vaccine

The hepatitis B vaccine may cause adverse reactions such as skin itching and swelling. These reactions are typically mild and gradually resolve within about one day. Applying a cold compress appropriately and closely observing the condition are usually sufficient.

3. Infection

If proper disinfection of the injection site is not maintained after vaccination, infection may occur, leading to itching. It is recommended to disinfect the area with alcohol or iodophor, which can effectively alleviate symptoms.

Note: If a child develops high fever, vomiting, or other symptoms after receiving the hepatitis B vaccine, and these symptoms persist for a prolonged period without improvement, prompt medical attention is advised. This could indicate an allergic reaction to the vaccine, which requires active treatment to prevent adverse outcomes.