Thank you for your query.
One does get rash over the body following upper respiratory tract
infection. However they are usually small as described by you (when you took your son to the pediatrician
). Large red blotchy rash
can be urticaria which is usually an allergic reaction
. Urticaria comes and goes. I suggest that you consult your doctor who may order some investigations and advise appropriate treatment. In the mean while you can give your son promethazine
syrup (Phenargan) 2.5 ml. three times a day till you see the doctor.
I hope I have answered your query to your satisfaction.
Wishing your son a speedy recovery.