How are skin and blood tests for allergies different?

Paul M. Ehrlich, MD
Allergy & Immunology
Science shows us that skin tests and blood tests for allergies don't really measure the same things. The antibodies that register in a blood test have a half-life of two days. They come and go without putting your immune system on a state of red alert. The ones that react in the skin have a half-life of six to eight weeks, which means that your body is ready to strike for a protracted period.
Asthma Allergies Children: A Parent's Guide

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Asthma Allergies Children: A Parent's Guide

Asthma and allergies are at epidemic proportions. It doesn't have to be that way. Two experienced pediatric allergists tell everything a conscientious parent needs to know about these conditions,...

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