White spots on sons skin

My son got a sore throat the other day, this consisted of a cough, his breathing being raspy and him not being able to talk a lot. The folllowing day he was a lot better, but today he started to really itch his skin, pretty much everywhere but mostly on his shoulders, back, stomach and thighs. The spots look like a heat rash or a rash from where you have been stung by stinging nettles. Is it simply a heat rash or could it be something else. He is really uncomfortable and woke up because of it.

[maatson]

Perhaps a viral rash but antibiotics do sometimes cause allergic rash too.Do consult your doc.