I know false positives are common, but I thought for the severity of the allergy false negatives were rare.

no help here somregal. When I had the scratch test on my back many years ago I reacted to EVERYTHING. I know my allergies were never that bad, figured it was something with the test.

Do you know what you are allergic to without the test being positive?

No, I had a few suspicions.  There were some foods I avoided for years that I started eating a while ago with no problems - I probably never needed to cut them out.  Now I know one for sure, but because it could be life threatening I'm actually more restricted than before I was tested.

I had it done on my arms.  I was allergic to about 40% of the substances for inhalants, and the positive and negative controls had the appropriate (or lack of) reactions.  For food nothing came up, so I was told I was good to eat everyhting they tested me for, although it wouldn't cover intolerances.

Allergist said it was weird too.  Whole bunch of tests were done.  Hopefully there will be some answer.

Yep, I have food allergies.  To the stuff I thought, but I need to avoid a whole group of stuff now too.  They don't know why the skin test didn't pick it up.

In that case that testing was harmful to me.  I was told to go ahead and eat stuff and because I did I'm now at a higher risk of having a life-threatening reaction.

When i was three years old my mother told me I developed a rash to penicillin and until several years ago I had never taken it again. Bcause I am allergic to a lot of antibiotics and the list of those I could safely take was getting short, and since my allergic reaction to penicilln was so many years ago, my family doctor decided I should be tested to see if I actually was allergic to penicillin. My skin test was negative and I was told by the allergist that I could safely take penicillin. I was in hospital a short time later and developed an infection at an IV site and was given penicillin ... and unfortunately, that allergist was VERY wrong!  My reaction involved only my skin, but my body turned into one giant hive.  I was told I looked like a lobster by one doctor ... and was told by several doctors it was the worst skin reaction they had ever seen.! The itch almost drove me crazy at times despite a high dose of prednisone, antihistamines,  pain medication, and steroid lotion. I found a cold shower with baking soda allowed me to rest for about two hours when again, I would have another cold shower to control the itch and pain! So that is my story about allergy testing ... my family doctor felt so bad that she had ever ordered the test!

As a child I was given a shot of penicillin. It was my first injection though I had been given pills. I went into a coma. Since then slwsys mentioned and i wear a bracelet. Years later a Dr. asked me if I had been tested and told me "everyone thinks they are allergic to penicillin". I pray I do not get one of those that will disregard a bracelet.

Pommom, that sounds horrible!

SG I kinda get why a doctor would question it, so many people use the term allergy when it isn't.  Hopefully doctors wouldn't just disregard it when it came time to actually prescribing/giving it!  It irrates me when people claim to have an allergy without actually having any evidence of a true allergy, as it does make people question when it is serious like in your case!

A few things constitue an allergy compared to a sensitivity . . . and I believe rash or hives is one that says it's an allergy.

I had an allergice reaction a year and a half ago, and my doctor told me never to take it again.  As a matter of fact, that was the beginning of the health issues I am going through today.  I'm not saying it had anything to do with it, or caused it, but everything has gone downhill since them.

I agree that allergy testing might not be 100% accurate, but I think if a person has actually had a reaction to something, they should avoid it.

I'm frustrated as I'm discovering foods that I cannot eat now.  Before it wasn't an issue, I avoided the major things within the group, but I didn't have to eliminate the entire group of foods.  I never had an issue with the 'hidden' things, but now I gotta eliminate those in case of sensitization :(

It's not as bad as trying to eat out with Celiac disease or something, but I'm just annoyed as there's a good chance if I wasn't told to go ahead and eat this, I wouldn't have to eliminate more things.

I have been reading a book called "The H.O.P.E. Formula by BRenda Watson . . . just going to quote a section on food sensitivities/allergies - it's long, but worth reading chemgal.  Just one persons perspective, but I found it interesting as I've been told that i have an allergy to cow's milk and cow's milk products, beef, and gluten grains.

From "The H.O.P.E. Formula" by Brenda Watson:

"The improper digeston of food (especially proteins) can lead ot an allergy-like response.  When undigested food particles enter the circulation through the walls of the intestine, the body responds as if they were foreign invaders, known as antigens.  An immune attack begins with the body producing antibodies (chemical bullets), which bind to the antigens, forming what are known as immune complexes.  When this occurs, there may be enough of an immune system imbalance to create indigestion.  In addition, stress can create a sympathetic dominance (fight or flight syndrome), which impairs digestion.  Both of these responses can increase intestinal permeability and lead to more food sensitivities.

As the breakdown of the digestive and elimination prcesses orrucs, an adverse reaction to any food can result.  Cerain foods show up more often than others as "allergens."  These include milk, soy, wheat, corn, east, sugar, eggs and the nightshade family, which consists of white potatoes, eggplant, tomatoes, chilli peppers, and garden peppers.  Tobacco and certain drugs are also included in the nightshade category.  Among the drugs so categorized are those containing atropine, belladonna and scopolamine, found in most sleeping pills.  It is important to know that a senstitivity or allergy to any food can develop, irregardless of nutritional value or lack of it.  It is also important to distinguis between an allergy and sensitivity.

Food allergies are easy to recognize.  They involve immediate, strong reactions to foods, whereas a sensitivity expreses itself in a much more subtle way.  Food sensitivites are delayed reactions to foods, wchih can occur anywhere from a few hours to a few days after exposure.  With the allergic response, the areas of the body affected by exposure to the allergen are generally limited to the air passages, skin and digestive tract.  When someone eats strawberries and develops hives, or is exposed to pollen and starts sneezing, this is a classic allergic response, the type for which allergists test with skin prick tests.  This type of reaction is an IgE (immunoglobulin E) antibody - mediated reaction to antigens in the food.  This is an acute allergy.

The IgG (as distince from IgE) antibody reaction to food is generally known as a food sensitivity rather than a food allergy.  The delayed food sensitivity in contrast to the acute allergy, may affect any organ or tissue of the body, resulting in a wide array of hpysical and emotional symptoms.  Such reactions, because they are delayed (by as much as three days)are frequently not recognized as food sensitivities.  It is common for eactive foods to e consumed frequently, to the point of addictoin.  By s\consuming such foods habitually, the body (unconsciously) avoids withdrawl symptoms.  Unfortunately, this also perpetuates digestive disorders.  When sensitive foods are eaten daily, the small intestine responds to the offenders by producing an antibody/antigen response.  With the passing of time, this response irritates the digestive lining by producing inflammation.  The response is analogous to wearing wool every day against the outer skin.  The skin would eventually react by becoming inflamed.  The same holds true for the lining of the gut.

If people avoid the foods to which they're senstivite, they may start to feel somewhat better, but if digestion insn't improved, they will develop new sensitivities.  On the other hand, if digestion is improved and toxins eliminated, sensitivities and allergies will be decrease or eliminated.

Both sensitivites and allergies may develop in response to anything in the environment - not just food.  The response to the antigin can affect any organ of the body.  The gut will always be involved, however.  Poor idgestion is both the cause and the ultimate result of the allergic response or sensitivity.  Significant stress will definitely lead to sympathetic dominance.  This decreases digestive efficieny (less enzymes, etc.) and increases intestinal permeability, setting the stag for food allergies or sensitivites.  The more food allergies or senstitivities, the more reactive the immune system becomes, creating more and more circulating antigen/antibody compleses.  These will promote inflammation throughout the body, especially in the GI tract, creating further problems.

With food allergies and sensitivies, there is an element of increased permeability (leaky gut) of the intestinal tract that plays a dominat role in initiating the process.  Undigested food particles have the effect of initiating an immune response (allergic reaction) when they have made their way into the bloodstream.  This can occur only when the lining of the intestine becomes porous.  This condition of increased permeability or porosity of the lining of the intestine is known as leaky gut syndrome."

Beloved, what I had was an IgE mediated allergic reaction.  That's what was picked up on the blood test as far as I understand (I had a short time with the doctor).

Leaky gut syndrone isn't recognized by conventional medicine.  It's become a huge fad in alternative medicine.  Intestine permeability is a real issue, but it's a serious one often involving a hospital stay.

Yes, this book is definitely written from an alternative medicine perspective.

I don't know if she differentiates between "allergens" and actual allergens, but sugar (glucose) cannot be an allergen.  Allergens are typically proteins, although other molecules can also be allergens, usually because they interact with a protein or a peptide (smaller than a protein) such as a nickel allergy.  Allergies to chemicals that are not proteins usually aren't IgE mediated.  Peanuts, treenuts, seafood, milk, eggs, soy and wheat are the major food allergens and account for 90% of food allergies.

The problem with the 'allergy testing' for food sensitivities is that we also produce antibodies that are actually responsible for preventing us from developing allergies.  Those tests often pick up those antibodies.  When someone has food intolerances, I understand why those tests are utilized, there aren't many other tests out there, and it at least gives a starting point of what foods to start examining.  It's why I had told you that there's a high rate of false positives.

I think this article is good:

http://www.sciencebasedmedicine.org/igg-food-intolerance-tests-what-does...

I found it interesting that things like overcoming a peanut allergy actually leads to an increase in an IgG molecule specific for peanuts.

What I was asking about in my OP was more about a serious allergic reaction, that had the potential to be anaphalaxis.