What is Chronic Urticaria?
Urticaria—the scientific name for hives—is an outbreak of red, swollen, and itchy welts that form on the skin. Hives appear suddenly and can appear anywhere on the body, including the face, lips and throat. They typically vary in size, and may join together to form larger welts. About 20 percent of the population develops hives at some point in their lives; often, these episodes last only a few hours.
For some people, however, the hives don’t go away (or they go away but recur frequently). This can last for months, and, in some cases, years. This type of recurring hives is called chronic urticaria. Although the condition is not life-threatening or contagious, it can cause distress, discomfort and pain for people who have it.
Chronic urticaria can occur in both genders and all ages, but tends to be somewhat more common in women ages 20-40.
What Causes Chronic Urticaria?
Urticaria is an allergic-like reaction of the skin triggered when the immune system releases histamine. It can be caused by the body’s reaction to certain allergens, or for unknown reasons.
Acute urticaria is an acute case of hives that lasts less than six weeks and is caused by triggers such as medications, foods and insect bites or stings.
Chronic urticaria is a chronic case of hives that last six weeks or more, and is often caused by a trigger that is difficult or impossible to identify. People with no known cause for their chronic hives may be diagnosed with Chronic Idiopathic Urticaria (CIU).
Angioedema is a form of hives where the swelling occurs beneath the skin rather than on the surface. Angioedema, found in about 30 percent of adults with chronic urticaria, is characterized by deep swelling around the eyes and lips.
Physical urticaria refers to several types of urticaria that are caused by physical triggers, such as heat, cold, exertion, emotional stress, alcohol, and pressure. The hives usually occur right where the skin was stimulated, and appear within an hour after exposure. For example: people with pressure urticaria get hives on certain parts of the body stimulated by constant physical pressure; people with cholinergic urticaria get hives caused by heat, exercise or emotional stress; and similarly, people with cold urticaria get hives on their skin where exposed to cold stimulus.
How is Chronic Urticaria Diagnosed?
Diagnosis begins with a careful medical history and physical exam. Your doctor will check first to make sure your chronic hives are not a symptom of a more serious illness such as hepatitis or hyperthyroidism. Once other illnesses are ruled out, the doctor will do a physical examination and ask questions about contact with substances that could have caused an allergic reaction. About 15 to 20 percent of chronic cases are caused by physical triggers such as cold, heat and exercise.
In the majority of chronic cases, however, the exact cause cannot be determined, so routine blood tests and allergy tests may be ineffective. If the medical history does not suggest what is causing the hives, other measures are taken: the patient is asked to keep a diary in order to record all activities, including everything ingested and occurrences of hives. Sometimes, the patient is put on an elimination diet to see if specific food is causing the hives. Often, though, these measures do not identify the specific cause of chronic hives. In these cases, the disease is called "idiopathic," meaning that there is no known cause.
How is Chronic Urticaria Treated and Managed?
The best treatment for urticaria is to identify and avoid the trigger, although this is often difficult to do. When the cause is unknown, medications can be used to control symptoms and prevent breakouts.
- Antihistamines. The first-line treatment recommended for urticaria is non-sedating H1 antihistamines, such as: loratadine (Claritin), fexofenadine (Allegra), and cetirizine (Zyrtec). These medications block H1 receptors, and are effective in reducing symptoms of hives with very few adverse effects reported.
If these medications don’t help, H2 antihistamines such as cimetidine or ranitidine (which block H2 receptors) may be added. Although H2 antihistamines are not effective for urticaria when used along, the combination of these two types of blockers sometimes provides more effective relief.
For more severe urticaria, the more potent antihistamines, such as diphenhydramine (Benadryl) and doxepin, may be used; however, these drugs tend to cause drowsiness and other side effects.
- Corticosteroids. For some people with chronic urticaria, antihistamines do not provide relief; in these cases, other forms of treatments, such as corticosteroids, may be prescribed. A short course of an oral corticosteroid or a single dose of an injectable steroid can be prescribed for an acute episode of urticaria that is nonresponsive to antihistamines. Because of serious side effects with prolonged use, long-term use of these medicates is avoided when possible. Doctors prescribe the lowest possible effective dose for the shortest period of time.
- Other therapies. Epinephrine injections may be given for people with severe hives or angioedema, especially when the throat is swollen.
For some people with chronic idiopathic urticaria, omalizumab (Xolair) may be prescribed. This treatment is the first biologic medicine approved for CIU, and can be effective for certain people with CIU who remain symptomatic despite treatment with H1 antihistamine therapy.
As with many conditions, treatment is most effective when established between a patient and their doctor. All treatment for chronic urticaria must be individualized and monitored under close medical supervision.
Also learn more about chronic urticaria from the American College of Asthma, Allergy & Immunology (ACAAI).
SOURCE: This information should not substitute for seeking responsible, professional medical care. First created 1995; updated 2015.
© Asthma and Allergy Foundation of America (AAFA) Editorial Board