Urticaria is another name for “Hives”. The condition affects about 20% of the population at some time in their lives. It is characterized by raised, red welts on the skin associated with itching that may be mild or severe. Scratching, alcoholic beverages, exercise, and hot showers may worsen the itching.
What causes Urticaria?
Hives may be categorized as acute, lasting less than 6 weeks, or chronic, lasting more than 6 weeks. Acute (new onset) hives is generally due to certain foods, medications, insect stings, and infections. Foods such as eggs, shellfish, and nuts are common causes. Medication such as Aspirin and Penicillin also are common causes of hives. Episodes of hives lasting longer than 6 weeks are called chronic. Even after detailed testing and investigation, about 80% of hives have no known cause. Sometimes the immune system is causing the release of chemicals such as histamine. In other cases, the hives may be a result of thyroid disease or other hormonal problems. In most chronic cases, the hives will gradually disappear over time. The most common reason for long-lasting hives is “Dermatographism”, which occurs in about 5% of the population. These hives appear within a few minutes after scratching along an area of skin. Dermatographism literally means, to write, which is why the hives occur on the same area where the scratch or stroke took place. Other causes are physical in nature including pressure from belts and constricting clothing such as sock bands, vibration, cold or heat, or even water (aquagenic). Cholinergic Urticaria is another form of hives, due to an increase in body temperature with sweating, exercise, hot showers, or anxiety.
There are many other less common causes of hives such that a complete evaluation by you doctor is recommended.
How is Urticaria Diagnosed?
Sometimes, the cause is obvious. For example, if one were to experience very small hives on their feet, shortly after taking a long hot shower, the cause would be easily identified. Because there are so many possible causes for urticaria, other cases require determined detective work on the part of the patient and physician. In some cases the cause cannot be identified. A single episode of uncomplicated urticaria does not usually need extensive testing. An episode of hives complicated by swelling or difficulty breathing needs immediate attention in the emergency room. If food allergy is suspected, a diary of foods eaten within a few hours before hives started may help. Chronic urticaria should be evaluated by an Allergist-Immunologist. The specialist will take a detailed history about your past medical history, family medical history, work and home environment, and medication you are taking. Sometimes x-rays or tests to analyze blood and urine are needed.
How is Urticaria treated?
In most cases, urticaria will improve with medications such as antihistamines. Non-sedating antihistamines are preferred because they are effective with minimal side effects. Frequently though, your physician may try a combination of 2 or 3 antihistamines. Severe episodes of urticaria may require temporary treatment with corticosteroid medication. If a causative factor can be identified, the best treatment is to avoid or eliminate that factor. For example, if a person experiences hives upon rolling in the grass, they should try and avoid exposure to that physical factor. For people with dermatographism, avoiding harsh soaps and frequent bathing will reduce the problem of dry skin, which can cause itching and scratching that can aggravate this condition.
Where can I find references and further information for Urticaria (Hives)?
American Academy of Allergy, Asthma, and Immunology
Web address: www.aaaai.org
American Academy of Dermatology
Web address: www.aad.org
Follow up with your doctor for more information regarding Urticaria (Hives)