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Causes of Hives

Hives (or urticaria) are red bumps or welts that appear on the skin, either in isolated areas or large portions of the body, during an allergic reaction. Typically they itch, burn or sting and can last for several hours before subsiding. Hives are relatively common and about 1 in 5 people will have an experience with them at some point in their lifetime. Since hives can be caused by so many different things, it can be tricky to pinpoint the exact cause, however it is necessary in order to avoid future episodes.

Hives can broken down into a few different types. Immunological, non-immunological, and idiopathic. Immunological hives are probably the easiest to identify. These are caused by changes that occur in the immune system (usually exposure to something that you are allergic to) that result in the release of a histamine. Non-immunological hives are also caused by a histamine being released into the blood stream, however, in these cases, the immune system has not been involved. Idiopathic hives are trickier in that they occur without warning and without a known cause. Sometimes idiopathic hives can be caused by stress or nerves.

Identifying the cause of hives is key to avoiding them in the future, but it can be incredibly difficult to pinpoint exactly what is causing them. The first question to ask yourself is whether or not you have introduced anything new to your system. Have you tried a new food or used a new laundry detergent? Any deviation from your normal routine should be considered a potential cause until you have identified the culprit. In the case that you have started using a new laundry detergent, soap or food item, discontinue use of the new item and see if your condition improves. If it improves when you remove the item and returns when you attempt to use it again, you’ve probably figured it out.

In many cases, however, there will be no cause that can be identified. Doctors estimate that roughly 95% of the patients they see who have chronic hives, there is no identifiable cause. Their immune systems are simply overly reactive. In these cases, the symptom (the hives) is all that needs to be treated. Usually treatment with an antihistamine will clear up the problem. If antihistamines do not correct the issue, some doctors will prescribe a short course of steroids, like cortisone which should clear the hives immediately and completely.


American Osteopathic College of Dermatology – Urticaria (hives)

Daniel More, MD. Causes of Hives. July 9, 2009.

Heather Brannon, MD. Causes of Hives. July 20, 2009.