Blood test for allergies

[PoppyBlunt]

Paediatrician wants to investigate possible allergies that my 3 yo might have. I've been asked to call the blood department at the hospital to book in blood tests.
I'm presuming they will know exactly what bloods to be doing and will have a note from the paediatrician, but we've been in a situation before where info regarding bloods wasn't relayed and the list didn't include everything that was needed. I knew what that was all about so could advocate and get it sorted. However,
allergies are all new to me though and I have no idea what bloods they should be doing. Any guidance would be hugely appreciated.

As an allergy mum myself, the only one you can determine via blood is wheat/gluten. The rest would need to be skin prick testing and even then only IgE allergies ( instant/hives/swelling/breathing difficulties) will show up.

Thanks @Coffeeandcrocs, that's really helpful. I'm confused why we're being sent for bloods then, especially as part of a host of bloods a few weeks ago he had the blood screen for gluten. Do you know the best way to allergy test? Keen to push for whatever is needed.

That's not true you can determine other ige allergies through bloods (my ds has been tested for peanut, milk, soya and egg). They can't detect non-ige allergies though.

I've had but and peanut allergies confirmed via blood tests.

Nut. Not but.

Elimination and reintroduction is the only way with non IgE allergies really I'm afraid!

I stand corrected on the blood test front, our private allergist said only wheat/gluten via bloods!

Thanks everyone, really helpful. Feels like a minefield and I know very little at the moment!