2. Rare Localised Reactions: Pain, Itching or Lymph Node Swelling
You might think “Arm sore? Yes.” But did you know that sometimes more unusual local reactions can occur — like extended pain, itching beyond the injection site, or swollen lymph nodes (especially under the arm) after the flu shot?
What to watch for
- Extended soreness that lasts more than 48–72 hours.
- Itching or rash near the shot location.
- Swollen lymph nodes near the injection area (less common, but documented).
Why it happens
The vaccine triggers the immune system locally. In some people, that localised reaction is stronger. According to an article from Healthworks, redness, pain or swelling, and fatigue are noted side-effects.
What to do
Use a clean, cool compress and over-the-counter pain relief if approved by your doctor.
Make sure this is logged in your health records — if you have a best health insurance plan that offers after-hours telemedicine, you might use that for guidance.
If you notice increasing pain, swelling or signs of infection (warmth, pus, spreading redness), contact your provider.
