What Causes Redness and Swelling in the Arm After Vaccination?

The redness and swelling of the arm after vaccination is generally caused by the stimulation of the ingredients in the vaccine on the skin. There is generally no need to worry about the redness and swelling of the arm after vaccination. You can observe more or apply heat. The redness and swelling will usually disappear soon. If the redness and swelling do not disappear and bleeding occurs, it is recommended to go to the hospital for examination and treatment. Usually, you need to observe for 30 minutes after vaccination before leaving. What causes redness and swelling of the arm after vaccination? It is normal for the arm to be red and swollen after vaccination, mainly due to the stimulation of certain ingredients in the vaccine solution on the skin. Redness, swelling, and induration usually occur within 24 hours after vaccination. This phenomenon usually disappears by itself in about 2 days. What to do if the arm is red and swollen after vaccination? 1. If the redness and swelling of the arm are not particularly severe, and the lump is not big, then local iodophor disinfection treatment can be performed. If the lump is large and has a clear sense of fluctuation, it is recommended to seek medical treatment promptly. 2. Pay attention to keeping the vaccination site clean and dry to avoid infection, or use water or fresh potato slices to apply externally to reduce swelling. In addition, the arm that has just been injected with the vaccine should not be used excessively to avoid bleeding. 3. You can apply a hot towel to the red and swollen area to reduce the redness and swelling. Each application lasts for about 10-15 minutes, and you can apply heat multiple times. Drink plenty of water, strengthen your body's resistance, eat a light diet, rest more, and avoid strenuous activities.