Each year I see hundreds of new patients with complaints of hives and swelling. Hives are intensely itchy skin rashes that resemble welts and can occur anywhere on the body. They typically arise without warning and about half the time, are accompanied by angioedema, a deeper swelling in the skin. "Urticaria" is the technical term for hives. These skin eruptions generally last for several hours but rarely for more than twenty four hours. Hives which come and go for more than six weeks are considered chronic urticaria (CU).
Acute hives are more short-lived (less than six weeks) and often don't require an allergy specialist. Foods or drugs are common triggers of acute urticaria but triggers associated with chronic urticaria are more difficult to identify. In fact, 80-90% of the time doctors are unable to determine the cause of chronic urticaria despite comprehensive testing.
A recent article published in "Annals of Allergy, Asthma and Immunology" reported on the uselessness of laboratory testing in the setting of chronic urticarial and angioedema. After analyzing the results of almost 2000 laboratory tests on 356 patients, they concluded that such testing was rarely helpful. I'm glad investigators J. A. Tarbox and associates researched this aspect of such a common ailment which remains poorly understood despite several decades of studies.
The good news is chronic urticaria is less difficult to manage now compared to 20 years ago. Most urticaria patients can achieve resolution and control of their skin eruptions after careful evaluation and treatment by a board certified allergist. New long acting and non-sedating antihistamines have proliferated since the 1980's. Allergists have strategically prescribed these medications often times in combination, allowing for improved outcomes and less need for sedating antihistamines (for example Benadryl) and oral steroids.
More than 20% of the adult U.S. population will have an urticarial experience at some point in their life. Chronic urticaria is rarely fatal but greatly impacts the quality of life of those who suffer from it. If over the counter (otc) antihistamines are not effective the itching and disfiguring skin eruptions (especially if angioedema accompanies it) may be debilitating. Work and school absenteeism is common. But chronic hives can also result in "presenteeism". Presenteeism occurs when an employee shows up for work despite feeling bad but is less productive because of their illness.
Current Management of Chronic Urticaria
Once hives and or swelling have lasted more than 6 weeks you should have a full evaluation by your doctor. Your doctor will conduct a thorough history and physical exam followed by lab tests. Although doctors only identify the source of the problem 10-20% of the time, treatment is successful in most circumstances.
The goal of your physician often shifts from finding the trigger of the hives, to successfully suppressing the rash and itching, allowing for you to experience productive and symptom free days. For many people the latter is a welcomed consolation. Yet others remain frustrated by not knowing what food, drug or other external factor is causing their problem.