Autoimmune urticaria is a medical condition in which an individual experiences chronic hives, or raised itchy welts, that are not caused by a specific allergen or other identifiable trigger. In this case, the hives could be related to an underlying autoimmune disorder such as lupus or thyroid disease. Chronic urticaria is generally not life-threatening but can be debilitating. Symptoms are treated with daily use of antihistamines or other medications, in addition to efforts to treat underlying autoimmune conditions as appropriate.
Urticaria is the medical term for the presence of hives, which are red or pink welts that arise spontaneously in the skin. This occurs when the body releases a chemical called histamine that causes blood plasma to leak from blood vessels in the skin. In some individuals, hives are triggered by conditions such as heat or stress. They can also be an allergic reaction to specific foods or to certain medications, such as codeine, aspirin, or nonsteroidal anti-inflammatory drugs like ibuprofen. Occasionally, hives occur with no apparent trigger.
Chronic urticaria refers to hives that last longer than six weeks or that disappear quickly but frequently recur. In autoimmune urticaria, the episodes of hives do not appear to have a specific trigger and are believed to indicate the presence of an autoimmune disorder, in which the individual's body responds to itself as a threat. This condition is diagnosed through a combination of a full medical history, a physical exam, and sometimes blood tests or skin tests.
Treatment of autoimmune urticaria typically consists of daily use of oral antihistamines to prevent the occurrence of hives. Often, doctors recommend a non-sedating antihistamine such as loratidine (brand name Claritin®) or fexofenadine (brand name Allegra®) as a first line of defense. Other types of antihistamines, which could cause drowsiness, include diphenhydramine (brand name Benadryl®) and chlorpheniramine (brand name Chlor-Trimeton®). In some cases, doctors might recommend the use of other medications to control autoimmune urticaria, including ranitidine (brand name Zantac®), short-term use of an oral corticosteroid such as prednisone, or certain tricylic antidepressants such as doxepin (brand name Zonalon®) to relieve itching.
In addition to autoimmune urticaria, hives can take many forms. A hive-like condition called angioedema involves swelling of the face, throat, or genitalia that might itch or burn and can sometimes be life-threatening. Physical urticaria refers to hives that occur in reaction to vibration, heat, sun exposure, pressure, or other physical stimuli but quickly disappear when the stimulus has ceased.