Ask the Expert: “I have hives. I must have allergies.”
April 28, 2015
Your Allergy Partners physician would likely respond to the above statement with a cautious “maybe.” Hives, like many of the responses of the body, can be caused by many stimuli, not just allergies. Take, for instance, the similar example of sneezing. Sneezing is a common allergic symptom; however, we all know that non-allergic stimuli can cause sneezing, from infections due to the common cold to irritants in the air (pepper, for example). In a likewise fashion, hives can be due to allergic and non-allergic causes.
Your Allergy Partners doctor will take a careful history and perform a thorough examination when considering whether your hives are due to an allergic reaction. Be prepared to answer questions on how long your symptoms have lasted, any recent exposures to new foods or medications, and whether you have experienced any other symptoms.
If you have had hives almost daily for six weeks or more, your allergist may use the term “chronic” to describe your condition. Hives lasting less than six weeks are called “acute”. The distinction between “acute” and “chronic” is important, as acute hives are more frequently associated with identifiable causes. If supported by the details of your history, allergy testing may be helpful in identifying causes of acute hives.
Many non-allergic conditions have been reported to be associated with chronic hives, including various infections, connective tissue diseases, thyroid dysfunction, and endocrine disorders. If your symptoms do not readily suggest one of these conditions, extensive laboratory testing is not typically warranted or necessary. Extensive testing is not cost-effective and does not appear to improve patient outcomes. In light of an unremarkable clinical history and physical examination, laboratory evaluation and allergy testing rarely identifies a cause for chronic hives.
Hives can be incredibly uncomfortable and frustrating. Hives typically improve with a regimen of antihistamines, regardless of the cause. For cases of chronic hives that do not respond to antihistamines, alternative treatments are available. A newly approved approach to chronic hives utilizes the medication Xolair (omalizumab). This medication was initially developed for patients suffering from moderate to severe allergic asthma, but has shown to be effective in chronic hives. With your input, your Allergy Partners physician can decide what testing and treatment options are best for you.