and red patch following MMR vaccination
is not uncommon.
In about 8-10% cases these reactions can be present. You have given him Ibuprofen( NSAID
) and it is the treatment of choice.
In most of the cases it subsides within 2-3 days.
Another possibility is improper technique. In this also only conservative management is needed.
Observe the fever spike and size of lesion. If it worsen consult your doctor immediately.