Doctor insights on:
Test Food Allergy
I've atopic dermatitis with white flaky itchy scalp when I don't eat soy fish diary nut my symptom get disappear my prick test food allergy is negative?
Avoid them: I am please something is helping your eczema. The relationship between food allergies and eczema is not well understoo. I would just encourage you to continue doing what works. D. ...Read more
Allergies occur when your immune system is triggered by envirionmental factors it should ignore--for example, pollen in the air, or dander on a cat or dog--and creates cells to fight against them. An allergic reaction typically causes itching, congestion, or drainage, and ...Read more
Simple/less simple: Many PCP's can review your symptoms and order a set of blood tests through a variety of labs that correlate well with formal skin testing. With these results in hand you could confirm or exclude some of the foods you are confirmed about. If this did not help in the long run, a secondary evaluation by an allergist may provide better information. ...Read more
History and testing: The best way to determine whether a patient has food allergy is to get a good history. We can perform skin testing and check blood levels to specific foods such as peanut, egg, milk, soy, or wheat that may be associated with allergic symptoms without testing to a whole food panel. Depending on the severity of a reaction, we can do an in office challenge and/or recommend avoidance. ...Read more
What to do with multiple food allergies and my doctor 3 times did prick test of food allergies but the result is negative please answer thanks?
Different issue: Negative skin test results for food allergies is very reliable to say you do not have ige mediated food allergy. Allergy blood tests would not be needed as are less accurate than skin tests. Other non-allergic issues such as food intolerance should be considered. Either way, if the food you eat causes symptoms, then please avoid it. ...Read more
Probably: You would usually get "shots" for interdermal testing, but most food allergys are not treated with "shots". They are treated with avoidance and oral drops. But the type of testing depends on the allergists. Some allergists use blood tests, others may use challange tests, which others may use interdermal testing. All are accepted methods of diagnosis. ...Read more
Dr. How to test for food allergies? How does allergy testing work in general? And what about non food allergy testing?
Two kinds: Of allergy testing - blood test for antibody levels and skin prick test (a small amount of the substance placed on a sharp tip that is pressed against the skin). The skin test is more likely to correlate with real allergy, however remember w both methods it can only suggest a possible allergy. Would leave interpretation up to ur allergist. ...Read more
Is a skin test for food allergies reliable? If I've tested negative can I assume that I am safe ingesting all types of foods?
Don't count on it: People can have adverse reactions to foods that are significant but have nothing to do with allergy. About 1/4 adults are intolerant to lactose sugar in regular milk & have a variety of symptoms. Red food dye #40 can give similar symptoms in many. Skin tests can be a guide, but maintaining a food diary & being vigilant about your changes in symptoms is often the best approach. ...Read more
RAST (Immunocap): Rast (aka immunocap) finds the same ige antibodies directed against food allergens as does skin testing. Rast is useful in patients who can't stop taking antihistamines & in patients who have severe eczema, dermatographism, or are very hairy. Igg rast or elisa has not been scientifically shown to be useful although it has its advocates. All tests are surrogates for elimination & oral challenge. ...Read more
If anaphylaxis to food is so rare how come it seems to be pretty common when researched? If a blood test for food allergy was neg should you worry?
Anaphylaxis: Even though one tests negative, one can still develop anaphylaxis by an overwhelming exposure to the food involved. ...Read more
Skin test for food allergies had a +2 reaction to milk and +to soy blood test came back negative still have issues w/milk what do I do?
Avoid it!: Allergy tests can be very useful but are not without a margin of error. Listen to your body, if a particular food does not agree with you, avoid it and find other foods that will provide the nutrients you are missing. The tricky thing with eliminating milk is making sure you are getting enough Vitamin D. Calcium and protein are other considerations in planning your diet. Best wishes! ...Read more
I recently had a Ige Blood Test for food allergies. The results can back at tomatoes: moderate Wheat: Low and Soy: Low. What does this mean?
Complicated: You cannot draw your conclusions from your testing only. If you have a positive test but eat the food every day without symptoms you are not allergic to that food. On the other hand if you have a low positive test but get hives every time you eat it you are allergic. The correct diagnosis is made by a combination of history and test results. You may need a supervised food challenge. ...Read more
When I eat diary produtcs and patato I get itchy scalp and thin hair but when don't eat symptoms get disappear prick test of food allergy is negative?
Great Detective work: The hardest part in diagnosing adverse reactions to foods is to tie in the right food with the symptoms. You have already found the offending foods. It doesn't matter that the skin test is negative. It appears that your symptoms are too mild to elicit a positive prick skin test or the antigen may have been changed when the testing material was prepared. Continue to avoid potato and dairy. ...Read more
Flushing reaction after eating foods, no commonality yet, throat weird. Mastocytosis negative, blood allergy test neg, food allergy on back neg. What is it?
Itchy throat and face constantly! Scared throat will swell shut! Use hypoallergenic, not on any meds and blood test for food allergy negatve?!
Skin prick test: You need to have a skin allergy test to the environmental allergens such as pollen grass trees and dust if you are allergic to some you might have pollen food cross reaction the good thing about allergic reaction is that usually when it comes it comes with the same manifestations most of the time means if your allergy symptoms are limited to what you mentioned they will stay like that. ...Read more
My prick test of food allergy is negative I've mites allergy but when I eat vegetables pulses diary products I get itchy scalp, weakness and thin hair?
Varies: There are some available blood tests your PCP could arrange for. They are not perfect, but can be useful when paired with your personal history. Allergists can also do skin tests that can also provide useful information. ...Read more
When doing a blood test for a food allergy, does the food have to be present in body? Or can it be eaten like 6 mos ago for example? Celiac too?
IgE antibodies: Are what being measured in your blood if we suspect allergy to specific foods, those antibodies are produced and stay there, means you were exposed and developed allergy to the food element in question, the food doesn't have to be currently present in your body, and could have been eaten years earlier ...Read more
Blood test for common food allergies negative does this mean there won't be any reactions to food or anaphylaxis?!
Maybe, maybe not: The test would suggest you have no indication of an allergic response to the items tested. This would suggest you will not be troubled by a bad reaction to those items for your life, but you can develop a food allergy or intolerance later in life. Most food allergies are not of the anaphylaxis type, but produce hives or other symptoms. ...Read more
If I have a positive Quest Diagnostics blood test for a food allergy, could a skin test give a stronger confirmation? So many positives for foods!
Blood tests: For food allergies are somewhat unreliable - as there are many problems with cross reactivities on the assays. Unless you have had a particular event like you were unable to breathe or throat swelling after eating a particular food and are sure there was nothing else causing it- then these results may not be clinically important. Pollen/ and environmental allergy testing is much more reliable. ...Read more
My blood test for common food allergies came back negative. Does this mean I do not have any food allergies and won't have anaphylaxis? Explain please
No guarantees: Not every food group was likely tested, nor is every food sensitivity detected by blood-work. Sorry, but food allergies are still an imperfect science. ...Read more
The skin on my face burns and itches as well as my throat. Doc did blood test for common food allergy-negative! Wont eat! Scared of anaphylaxis now!
2nd opinion: Inhalant or food allergies do not cause prolonged facial burning or itching. However throat itching (provided no throat closure) can be present if someone has eaten a food and particularly certain fruits. The latter is due to cross-sensitivity to a pollen (birch, ragweed). You need to consult a b/c allergist to pin this down. I usually test with the actual fruits instead of extracts. ...Read more
Skin Prick Testing: Food allergies are diagnosed first by getting a detailed clinical history of reaction. If history is concerning then skin prick testing and/or serum IgE testing to concerning foods will be drawn. Skin prick testing usually done first followed by serum testing to follow sensitivity over time. Prick to prick testing with actual food is also helpful to help clarify risk. See Allergist for details. ...Read more
Neither: Skin testing and blood test (serum specific ige) have different sensitivities and specificities. Either or both must be interpretted in light of the clinical picture. Frequently, patients with positive tests are not allergic and an oral challenge under the supervision of a board certified allergist familiar with oral challenges and treatment of anaphylaxis is needed. ...Read more
Depends: It depends on which type of food allergy testing your doctor is ordered. There are 2 types of food allergy test allergist like us do. Ige mediated food allergy (but not igg because igg food test is unproven) can be done by skin prick test or blood test, which is not interfered by cortisone. However cortisone will interfere with food patch test, which test cell mediated food allergy. ...Read more
Sure, but...: There's more to milk than just lactose. Intolerance to milk may include problems with milk proteins or even with processing the fat component of milk. If your problem resolves with concomittant use of lactase enzyme when eating the same milk products (that cause gas & diarrhea in the absence of lactase) then lactose intolerance is likely. More elegant lactose intolerance testing is available too. ...Read more
To find out what foods I can eat do I have to do a separate set of food allergy test or with the 1st test.
See Allergist: Blood tests for food allergy are notoriously difficult to interpret (and often misinterpreted) without substantial information about your food history. Do not eliminate foods from your diet that you have been tolerating based solely on the blood test. If possible, skin testing and oral food challenges need to be incorporated into a complete work up. In short, discuss with an Allergist. ...Read more
We are trying to do the food allergy test on my 6 month old but he won't eat any of the vegetables we've tried. What do I do?
Plan B: There are various ways to get information on food alllergies for your child. Bloodwork can provide suggestion of food allerrgies. Skin tests, though uncomfortable, provide added info. The food challange is by far the most reliable of the three but requires babies cooperation. I generally don't food test kids this young unless they have eczema, chronic nasal drainage & infections etc. ...Read more