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blood test for food allgergy

My food allgery started 3 years ago and I am under medication. Recently I had my blood test and it indicate I am not allegic to certain food ( such pork and tomato ), but every time i eat them,  my face , neck and body being red and swollen with hives. So, I am wondering how accurate is the blood test for food allgergy ?  

Now, I can't eat any food without taking my medication.

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Avatar universal
Many people do not trust blood allergy testing (generally speaking about air born allergens) saying that it is unreliable with lots of false negatives mostly, but some false positives.  I see no reason why it should be more reliable for food testing.  The best food testing is a Food Challenge.  An allergist gives you small amounts of suspected foods and watches for reactions.  It is a long  and expensive process and usually only done for extreme cases.  

The suggestion of keeping a food diary is a good one.  Keep track of all the foods that cause reactions, then as Caryopteris said, avoid them.  What point is there in eating a food (even in the smallest of amounts) that makes you miserable (whether it is a true allergy or not).  Hives usually do indicate an IgE mediated allergic reaction though, although there are non-IgE mediated allergic reactions like acid reflux and a few others.  Some people with peanut allergy can just inhale a very small amount of a shell and go into anaphalaxis shock.  If you think you are allergic to a food it is best to avoid it altogether.

I hope that you get the answers you need.  
Helpful - 0
1340994 tn?1374193977
My doctor says I have food allergies but doesn't like the tests.  He says I react to the foods and get better when I stop them, so therefore I have food allergies.  I feel good when I don't eat them, so I don't eat them.  
Helpful - 0
1355118 tn?1298564879
MEDICAL PROFESSIONAL
Hi, welcome to the forum, determination of the food you are allergic to, is one of the challenges which you need to pass through. The common existing food allergens are Peanut flour, peanut butter, Powdered egg white, Powdered/fresh milk Soy milk, soy flour Wheat breads, flour etc.

As allergic reactions are IgE mediated, blood tests will show increase in these levels secondary to a food allergy. The problem with the food allergy testing is sometimes the amount of food they challenge with may be not sufficient to elicit any allergic reactions.

When such food are consumed in large quantities can elicit allergic reaction in the form of hives, redness of skin, itching etc. You need to note down such food also in your diary and avoid the intake in future.

I suggest you to consult skin specialist/ immunologist for further line of management. Take care and regards.
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