Question
Why does the arm appear red and swollen after children receive the Hepatitis B vaccine?
Answer
After children receive the Hepatitis B vaccine, they may experience mild redness, warmth, pain, or hardness at the injection site as common side effects. These symptoms usually appear within 24 hours after vaccination and resolve spontaneously within a few hours to several days. If the redness is severe, you can relieve the symptoms by applying heat compresses twice a day, each for about 5 minutes. Additionally, change your underwear frequently to avoid infection. If there is regional infection, you can use gentian violet solution for treatment. In rare cases, children may experience more severe reactions such as high fever, headache, vomiting, or abdominal pain. If these occur, seek medical help immediately. Generally, when the body temperature returns to normal, other symptoms will also subside.