suspected allergy to fish and hazelnuts

[Madzia123]

Hi
My DS just under 3 and he had (we think) allergy reaction to fish and hazelnuts. He vomited after very little amount of fish (tea spoon of rice and fish) and the same for one soldier with hazelnut butter on it. I bought Piriton and we are seeing GP on Friday. DS has mild eczema and his dad has allergy or egg intolerance (we are not sure) so I should have expected this. I didn't and I'm worrying myself sick.
I will be grateful for any advice you can give, esp. how to get him tested etc. We have private medical but I know that they will not cover chronic conditions so probably they will pay for first diagnosis only....
Can anyone tell me what to expect from an allergist? I know that they can run tests and let you know what food to avoid and prescribe Epipens. Is there any other help available?

Thank you

Hi, I answered you on another thread so will copy and paste here instead

Hi Madzia123, with my dd she had skin prick testing at the hospital via a paediatrician regarding her allergies. We are with NHS only. Due to her life threatening peanut allergy and other multiple more minor allergies we have seen them a lot through her lifetime. We found out at around your ds's age when my dd reacted to a peanut her brother kindly gave her.
Please don't worry, just take one step at a time. My dd is a teen now and manages lovely despite her allergies.
I personally learnt lots over the internet and with my dd I did not and do not always find the allergy appointments that helpful although we always attend and sometimes it is useful for a little guidance or protocol for school. The skin prick tests as a general step was the best but used as a guide only.
There is nothing better than what your ds's body is telling you and I personally find keeping a food diary is very useful to pin point triggers/reactions.
Skin prick tests involve putting tiny drops of solution containing the allergen on the skin and then pricking the skin to let the solutions in. You then wait and dependant on the size of the hive or wheal they will read it and measure and tell you whether they are allergic or not. How allergic and what to do about each food item. One important bit of info prior the the skin prick tests is to not let him have any piriton (here) www.allergyuk.org/diagnosis--testing-of-allergy/skin-testing
Dd had massive hives to peanuts and more minor ones to other foods which some she can tolerate and some she can't. They can test all sorts like pollen, dustmite and pet dander ect so have a think of the most important ones you may like done as well in case they ask. My dd had bad eczema, turned out to have dustmite/pollen allergies too which are ideal to know so you can take steps in your home to help.
Their advice on things will change from consultant to consultant and also dependant on advice fads at the time. I am possibly a bit outdated now as dd has not had skin pricks for years. She did however have a blood test a few months back where they can also use to test allergies to specific things. This time we were checking out salmon and a few other things as she was getting an itchy mouth but it turned out to be negative. I am still unsure and will try her eating it again as it may have been the sweet potato she had with it. Going by my dd she can still have small itchy mouth type reactions to things that come up negative but I think it is oral allergy syndrome where they react to the similar pollen like proteins in fruit/salad items/raw veg due to dd's pollen allergy. She also has these weird things happen more so when under the weather.
If he turns out to have anaphylaxis then the anaphylaxis campaign is a great source of information www.anaphylaxis.org.uk/
Our allergy appointments even gave out photocopies from their site for info. Hope that helps a little, goodluck at the doctors