ZocdocAnswersWhy do people get hives?

Question

Why do people get hives?

I got hives on my arms last week. Went away pretty quick but it was really uncomfortable and I don?t want to ever get them again. What could have caused hives on my arm? Something I ate? Something I touched?

Answer

The medical term for "hives" is urticaria, which refers to the pale/red raised itchy rash that occurs, often associated with an allergic response. There are actually different general categories of urticaria; acute and chronic. Acute urticaria is almost always due to an allergic response. Chronic urticaria (usually lasting more than 6 weeks) on the other hand is rarely due to an allergic source. Judging by the information that you have provided, it doesn't sound like you have a case of chronic urticaria. However, without being able to examine you, or take a thorough history, I won't be able to give you an exact answer about what may have caused your urticaria in the first place. The swelling and itchy rash that occurs is secondary to histamine release from mast cells (regardless of the initial causative insult). This response can be modulated by both over the counter and prescription medications called anti-histamines. However the best way to avoid developing hives again is by identifying what actually caused the response in the first place, and avoiding it in the future. I would recommend making an appointment with an allergist to have them evaluate you and take a thorough history. They may even do some allergy testing at that visit. I hope this was helpful, and I wish you all the best.

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