Swollen red face caused by plant sap - what can we do?

[Millarkie]

Turning to mumsnet whilst I wait to find out if we can id the plant.
Ds's 'friend' rubbed some 'stuff from inside a plant' all over his face last night. We washed it but this morning his face is red and swollen and sore. I've given him piriton and we are trying to work out which plant it is (hopefully not Giant Hogweed).
Any ideas of how to deal with it? (Or which plant it could be?)

How much piriton have you given? If its a bad reaction may need to give higher dose or need different meds from hosp. If the piritons going to work usually does so pretty fast.

I'd seek medical advice.

Hope he is ok.

medical advice for sure.

I'm back - sorry to post and run!

The piriton worked - swelling went down, redness is paler but still there. Other child's mum tracked down the plant which is a climber - ivy-like but not ivy (leaves longer and not so lobed), still not identified, but I guess irritant rather than in the league of Hogweed, thank goodness.
He's running around demanding biscuits so not too bad - and I've covered him in hypoallergenic sunblock just in case it's made him photosensitive.
He has had bad swelling from reactions to unknown allergens before so we had strong anti-histamines, epipens etc to hand just in case - but thanks for the support.

I'm glad it worked. Good idea about the sunblock.

Well we relaxed too soon. 7pm we noticed that ds had a row of blisters across his forehead and another set across his nose We've given him calpol but dh took him (and the plant) to A and E because we were worried about the extent of the blistering and whether calpol would be sufficient pain relief.
Have been waiting for dh to ring and update for hours now..

ow what did they say?

He came home at midnight having been seen by a plastic surgeon. Plastic surgeon has given him some cream to use and told him not to get water on his face, the damage to the skin isn't all the way 'through' but he needs to see the practice nurse on Tuesday (I guess the blisters will have popped by then and he will have an open sore across his face ) We are dosing him with paracetamol/ibruprofen and he is still sleeping now.
Not sure what to do about school tomorrow. Think he would be ok for lessons if pain relief is enough, but don't want to think about him standing around in sunshine at lunch/PE etc.

oh blimey. Poor lad and poor you. I'd probably keep him off for a couple of days just to be on the safe side.