Hives in Vancouver, WA
Hives, also known as urticaria, affects about 20 percent of the population during some point in their lives. An episode can start off as mild or severe itching, followed by red, swollen welts. Avoid scratching, exercising, emotional stress, and drinking alcohol, as these may worsen itching.
They may persist anywhere from a few minutes to several hours, days, or even weeks. However, each individual welt should last no more than 24 hours.
Types of Urticaria
Acute episodes last for 6 weeks or less. They’re generally the result of certain foods and additives, medications, insect stings, infections, and blood transfusions. Eggs, nuts, and shellfish are common causes. Medications like aspirin and antibiotics (especially penicillin and sulfa) are also culprits. Infections causing hives range from the common cold to strep throat, infectious mononucleosis, and hepatitis. Most of the time, the hives go away when the triggers do.
Chronic episodes last more than 6 weeks. Often the cause cannot be identified despite detailed testing, which is when the condition is called idiopathic urticaria. Approximately 50 percent of cases reveal the immune system releasing chemicals like histamine. The other half tend to have chronic urticaria associated with thyroid disease or other hormonal issues. More rarely, it’s been associated with cancer. Usually, the hives disappear over time.
Physical urticaria stems, as the name suggests, from “physical” causes. Dermographism is the most common reason for long-term urticaria. These hives appear within a few minutes of scratching. Most often, the rash is linear and follows the direction of the scratching. Delayed pressure urticaria is also possible. This refers to swelling on places that receive constant pressure from belts and constricting clothing. The cold urticaria that comes from exposure to low temperature followed by re-warming can be life-threatening if there’s a generalized body cooling, like after a plunge into a swimming pool. Cholinergic urticarial happens from increased body temperature with sweating, exercise, hot showers, and/or anxiety. Sun-induced urticaria can start just a few minutes after exposure.
Certain types of chronic hives are more painful than they are itchy. They may leave a bruise as they disappear, and individual hives could last even longer than 24 hours. In such cases, vasculitis, or inflammation of the blood vessels, may be responsible.
How Are Causes of Urticaria Determined?
The cause is sometimes obvious—a person eats peanuts or shrimp and then develops hives right away. Since there are so many possibilities, other cases require detective work for both the patient and physician. Sometimes, the cause can simply not be identified.
Chronic urticaria should be evaluated by an allergist-immunologist. The specialist will take a detailed history about your and your family’s medical history, your environments, and your medications. Skin testing may be useful, or a skin biopsy could be helpful when vasculitis is suspected.
What Does Treatment Involve?
Urticaria usually improves with antihistamines and similar medications. Low-sedating or non-sedating are preferred since they bring minimal side effects. Your physician may prescribe 2 or 3 antihistamines. Severe episodes might warrant temporary treatment with prednisone or other corticosteroid medication. If a cause can be identified, the best treatment is avoiding it. For example, if a specific food is the problem, that food should be eliminated from your diet.
Those with physical urticaria should avoid exposure to the cause where possible. Patients with solar urticaria should wear protective clothing and use sunscreen outside. Loose-fitting clothes help relieve pressure urticaria. People with cold air urticaria shouldn’t swim alone, and those who have it to a severe degree should not swim at all. Cold air exposure should be avoided when possible; warm clothing worn for unavoidable exposure to cold air. For people with dermographism, avoiding harsh soaps and frequent bathing will reduce the problem of dry skin, which can cause itching and scratching that can aggravate this condition.
This article is taken in whole or in part from the American College of Allergy, Asthma, and Immunology. For further information, visit www.acaai.org.
Contact our physicians to get your hives under control. They can find out what caused your condition and what to do about it.