I've gone through allergy testing, but it was quite a few years ago... The way it was done (at that time, anyway), was that after a specified period of time during which you avoid eating/drinking a whole lot of different things, the doc (or was it the nurse -- I forget!) injected tiny little amounts of various substances in nice little rows/columns all over my back and down one arm. They, of course, keep track of what is injected where. After a specified period of time, they look at all of the injection sites to see if there has been any reaction. If so, it means you're allergic to that particular substance. The level of reaction determines the level of allergy. In my case, I didn't have any reactions during the originally specified time, but a day or so later, a couple of the injection sites on my arm had turned red. So, that meant I had a delayed reaction -- and from what the doc told me at the time, shots don't help allergies to things for which you have a delayed reaction.

I just had it done last spring. Stubborn problems.

Started with arm patch test. It was not so bad.

Since it was inconclusive, they did a back test. That was uncomfortable, and I had to go, I think 72 hours with no shower. They had to get 3 "reads" of the test sites, the third being 72 hours out.

I wanted the blood test, which I heard is simpler. But my allergist does not like them. He said the patch tests are more conclusive. But I would still like to get the blood testing done at some point.

The usual way is to inject tiny, tiny amounts of a diluted solution of the most common allergens. Then the site is watched and the amount of reaction is noted. I don't know how it is now, but it used to be 0 was no reaction, up to +4 as a big reaction. It just feels like a series of pin pricks.

On my first testing, I reacted to a lot of things, but the doctor decided that if he treated me for the seven worse, my body might be able to handle the rest. Several years later, I started having summer problems. The testing was done again and grass pollen was the problem. This was added to the mix and one of the others, which now showed little reaction, was dropped.

Once the allergen or allergens is identified, a solution made up just for that patient is created. And a series of shots is given to gradually get the body to adjust to tiny amounts. Then the solution is made less and less dilute until hopefully, the patient's body can handle the problem alone.

Few, if any, doctors will allow you to give yourself the shots. The amount must be strictly controled. Patients can go into anapylactic shock if they are accidently given the incorrect dose. It's not something you want to risk unless there is no way that you could get to the doctor's office regularly. And to be effective, the shots must be given on a regular schedule.

It's my understanding that a blood test merely says, Yep, you're allergic to something. It is not able to identify the exact substance.

A good allergist needs to be a good detective.

I was raised in a home in a pecan grove. It wasn't surprising that I was extremely allergic to pecan pollen. However, by the time I was tested, I had married and moved blocks from the nearest pecan tree. It didn't interfer with my life anymore except when I visited my mother those few weeks in the spring.

Good luck!
PB