Hives Defined

• Hives (urticaria) involve an outbreak of red blotches, welts or pimples on the skin. They appear suddenly and are usually a result of an allergic reaction. Hives can be very uncomfortable, causing itching and soreness. They can show up anywhere on the skin, even inside the mouth. They can also cause swelling of the eyes and throat. Hives can last anywhere from a couple of hours to several days. A condition similar to hives is angioedema, in which the swelling occurs beneath the skin and is most noticeable around the mouth and eyes.
  
  

Allergies That Cause Hives

• Hives appear when histamine is released from skin cells surrounding a blood vessel, causing blood plasma to leak out. Only about 5 percent to 10 percent of cases of hives are caused by allergic reactions. The most common allergic reaction to produce hives is a pet allergy. Hives can also be caused by allergies to medications, such as aspirin, antibiotics, ibuprofen, codeine and some hypertension (blood pressure) medications. For people who suffer with severe seasonal allergies, coming into direct contact with fungus spores or pollen can also cause hives to break out. Other allergens include latex, insect bites and stings, and foods such as nuts, eggs, milk and shellfish. You may have a greater risk of experiencing hives or angioedema if you have had them before, have a family history of them, suffer from thyroid disease, lupus or lymphoma, or have experienced other allergic reactions in the past.
  
  

Treatment

• If you are experiencing mild symptoms of hives, you may not need to seek medical treatment. You could use topical applications, such as calamine lotion, to ease the discomfort of itching. Over-the-counter antihistamines, such as Benadryl, Claritin, Tavist or Alavert, may also be beneficial for reducing itching and swelling caused by the production of histamine. Remember that some antihistamines may cause you to feel drowsy. Prescription medications that are often prescribed for hives and angioedema include Allegra and Zyrtec.