MMR site.

[Titsalinabumsquash]

My DS3 had his preschool boosters on Wednesday and his normally slim upper arm has swollen to 3 times its size, although the picture doesn't show it its tinged purple with bruising, I don't know of this is the mmr side or the 5 in 1 side but it's sore and big enough to strain against his tshirt sleeve that's usually quite loose.
Should o be concerned?

I would take him to the GP just to check. They don't normally go as red as that

ouch! That looks sore. :( You can report reactions here:

MHRA yellow card

Maybe ask if there is anything you can do to relieve it. Poor boy

The going to see the nurse at the Dr's surgery after nursery to make sure he hasn't got cellulitis. Poor wee soul, he's only just come out of hospital for a suspected appendicitis!

:(

They said just to keep an eye, if it spreads or changes in anyway then call ooh.

Dd had a similar reaction. It was treated as cellulitis, but I actually think it was just a reaction to the injection.

Draw round in biro and watch out for spreading or getting redder or hotter.