ZocdocAnswersHow did I end up having hives all over my body?

Question

How did I end up having hives all over my body?

I ended up with hives out of the blue last April. I don't know what caused the hives to break out because I didn't eat anything that I was allergic to. The hives lasted on my body for three days. Should I have an allergy test done?

Answer

Hives can be a very uncomfortable outbreak to endure. Hives are a manifestation of an allergic reaction. To explain: you have special immune cells called Mast cells that release a substance called histamine into your blood stream and tissues. Histamine causes blood vessels to dilate, and skin to be irritated and become very itchy. The end result is hives. The question is what set it off? Since it happened so long ago, and you haven't had any episodes since, I think its okay to just watch and wait. It may be that the allergic side of your immune system got set off by some environmental allergen, but you haven't seen this substance since. If you have a second episode of hives, then I think you should schedule an appointment with an allergist to have allergy testing done. Otherwise, I think you can probably treat this one time as a free-be. In the mean time, make sure to see you primary care physician in the next month or so. Bring this issue up with him or her. Your doctor will likely want a description of your skin lesions, symptoms you had at the time, and any foods, plants or other environmental factors you were exposed to during this time.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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