What causes those itchy hives and what can be done about them?
Hives are those awful, itchy red raised welts on your skin. They are caused when mast cells in your skin are triggered to release histamine.
There are two types of hives, short-term hives (acute urticaria) and long-term hives (chronic urticaria). If you have had hives for less than 6 weeks, you probably have acute urticaria.
Acute urticaria can be triggered by things such as eating a certain food or drug, insect bites, and infections.
Urticaria can be associated with more serious symptoms such as angioedema (swelling of the lips, eyelids, tongue or other part of the body), nausea, vomiting, abdominal cramping, light headedness, wheezing or shortness of breath. These serious symptoms can be signs of anaphylaxis, a life-threatening allergic reaction that required immediate medical attention. If you are experiencing serious symptoms with your hives, seek immediate medical attention by calling 911.
While swelling and hives can be signs of anaphylaxis, it is more likely that your hives are caused by something else. As long as you don’t have any of the other symptoms of anaphylaxis, you can probably wait until you can get a doctor’s appointment to fin out the cause.
If you have had hives for more than 6 weeks, you probably have chronic urticaria. Chronic urticaria can be caused by an autoimmune condition, thyroid problems or cancer. Or, it could be due to a physical urticaria, a non-allergic trigger. Examples of physical urticaria include developing hives after scratching or rubbing, tight clothes, sweating or being too hot or too cold, swelling from vibration, and in some cases, exposure to sun or water.
Hives are usually treated with antihistamines such as Benadryl, Claritin, Zyrtec, Allegra and Xyzal. If antihistamines don’t work, your physician may recommend a few days of corticosteroids. For severe or difficult to treat hives, some patients may require Xolair injections or immune modulators such as cyclosporine.