Allergies

Hives

Hives, or urticaria, are elevated, red, itchy blotches on the skin. Hives may occur suddenly, last a short time and go away, or they may last a long time (>6 weeks), at which point they are called chronic. Hives can be accompanied by more severe swelling which can occur underneath the skin, especially in the soft tissues around the eyes, lips, hands and feet. This form of swelling is referred to as angioedema. Hives and angioedema may occur alone or together. Sudden causes of hives include medications such as penicillin, a viral infection, an insect sting or from eating certain foods such as eggs, peanuts, tomatoes, walnuts, and fish. Sudden onset of hives may be due to medications or certain foods such as eggs, peanuts, tomatoes, walnuts, and fish

Most patients who come to the allergist's office with hives have suffered with them almost on a daily basis for six weeks or more and are therefore chronic in nature. Often in these cases, no underlying cause such as food, infection, other underlying diseases or drug reaction can be identified, and we call these hives "idiopathic" or of unknown cause. Chronic hives usually is well controlled with antihistamines, but may require combinations of medication to control them. For many people, hives will go away over period of five years.

Treatment

On your first visit, the allergist will take a careful history and perform a physical examination to rule out an underlying illness or disorder as the cause of your hives. For the same purpose, he/she may perform certain laboratory tests. Allergy skin testing in NOT indicated for evaluation of hives and angioedema unless it is being used to evaluate for concomitant allergic rhinitis or a specific food allergy. Treatment usually begins with antihistamines. Atarax (hydroxyzine), Benadryl or Zyrtec are some effective antihistamines used for the initial treatment of hives. If one antihistamine does not seem to work, another other medications may be added or substituted some time during the course of treatment.

Some patients may experience the onset of their hives following exposure to physical factors such as extreme cold or sunlight, exercise, or following direct pressure on the skin (for example, from a tight belt or bra strap). In these cases, it may be wise to avoid physical factors that are known to provoke hives.

In most cases, hives and angioedema can be controlled by ruling out underlying causes and treating with proper medication.

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Last Reviewed: Oct 19, 2010

David I Bernstein, MD
Professor of Medicine
College of Medicine
University of Cincinnati

I Leonard Bernstein, MD
Clinical Professor Emeritus
College of Medicine
University of Cincinnati

Jonathan Bernstein, MD
Associate Professor of Medicine
College of Medicine
University of Cincinnati