Thanks, am waiting at dr's now. I think it might have been pruritis too (looked most likely with dr google!). I shall also ask about best antihistamine for future use. I also left a message for my daycarer to call me so I can discuss with her.
I'm pretty sure it wasn't food cos he's always had a classic outbreak of hives with that (from egg anyway, the treenut reaction we don't know)... But seasonal stuff is definitely a possibility. I think I also need to cull some pj's. He was in some with a bit of polyester... Where I normally stick to all cotton.
It's a horrible thing alright.