Rash on DS

[AlaskaBird]

Anyone have any ideas what this could be, please?
It comes up sporadically and it's itchy. No lumps or bumps so not bites.
Only on front of torso.
I'm thinking GP visit...

Sorry - more info - he's completely well in himself and he's 13.

Bump

I don’t have any useful advice but my DD (3) has something very similar on his feet right now. I was wondering if it was from the heat as he’s been in socks all day

DS not DD

Did it start with a single patch? Looks like it could be pityriasis rosea but I'd take a closer picture and show a pharmacist, they are fab for rash questions.

oakleystreet no, it came up like that all at once. It disappears and then comes back sporadically; that photo was just after he'd had a shower.

Hives? Is he reacting to something?

Could it be pityriasis rosea? The way the patches are aligned looks a little like that (a 'Christmas tree' pattern).

Sorry I missed that that had already been suggested!

Hives.
Also known as urticaria.
Could be allergic to shower gel for example; or can be an immune system over enthusiastic response to a minor virus.

Could it be a reaction to the soap or deodorant or by having the water to warm?