From the Guidelines
Redness and swelling after a Tdap vaccine typically last 1-3 days, though it can occasionally persist for up to a week. These local reactions are common and normal, affecting about 1 in 4 recipients, as reported in a study published in Pediatrics in 2006 1. The affected area may be warm to touch, slightly painful, and measure anywhere from 1-5 centimeters in diameter.
Managing Local Reactions
To manage these symptoms, you can:
- Apply a clean, cool washcloth to the injection site
- Take over-the-counter pain relievers like acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) according to package directions
- Gently exercise the arm to reduce stiffness These reactions occur because the vaccine stimulates your immune system to produce protective antibodies, causing temporary inflammation at the injection site.
Monitoring for Unusual Reactions
If redness and swelling worsen after 3 days, spread beyond the general injection area, or are accompanied by high fever or severe pain, you should contact your healthcare provider as these could indicate an unusual reaction requiring medical attention, as noted in the study on Boostrix, a Tdap vaccine, published in Pediatrics in 2006 1. The study found that severe degrees of redness, swelling, or increased mid–upper arm circumference occurred in less than 4% of vaccine recipients.
From the Research
Redness and Swelling after Tdap Vaccination
- The duration of redness and swelling after Tdap vaccination can vary, but local reactions are usually mild and limited to the injection site 2.
- A study found that local reactions with an area of redness or discoloration > or =5 cm in diameter occurred in 35% of children in the placebo group, and the reactions typically resolved within 2-3 days 3.
- Another study noted that most allergic reactions to vaccines, including Tdap, are reported within a few days of vaccination, but the exact duration of redness and swelling is not specified 4.
- Prophylactic use of acetaminophen or ibuprofen may reduce the incidence of adverse reactions, including redness and swelling, in young infants receiving DTwP vaccine, but the effect on Tdap vaccination is not well established 5, 6.
- The frequency and severity of local reactions, including redness and swelling, may increase with successive doses of Tdap vaccine, but the duration of these reactions is typically short-lived 3.