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At a Glance
Why Get Tested?
When to Get Tested?
When you have symptoms such as flushing, nausea, throat swelling or low blood pressure that may be due to a life-threatening allergic reaction; sometimes when your healthcare practitioner suspects that you have mastocytosis or mast cell activation
A blood sample drawn from a vein in your arm or a 24-hour urine collection
Test Preparation Needed?
None for anaphylaxis, but timing of the sample very soon after the beginning of symptoms is important. If testing is done for other conditions, you may be instructed to refrain from taking antihistamine and other medications. This should be discussed with your healthcare practitioner.