Hives, which are sometimes called urticaria, are red, itchy, raised bumps appears on any skin surface. Many episodes of hives occur as a result of allergic reactions and lasts for less than 6 weeks, while other causes have nothing to do with allergies at all.

Allergic Urticaria: Hives in Allergic Reactions

In allergic reactions, an allergen coming from outside sources such as food, beverages, medicine, insect venom, chemicals, pollens, and dust particles, binds with specific IgE antibodies produced by the body. Histamine is released from mast cells that are abundant in the skin and capillary linings. Rashes and wheals break out when blood plasma leaks out from the capillaries and into the epidermis due to the release of chemical mediators of inflammation (e.g. histamine). In some cases, the fluid seeps deeper into the dermis resulting into angioedema. Acute allergic urticaria becomes apparent within minutes after exposure to the allergen and lasts for weeks, but usually less than 6 weeks. Hives that are present for more than 6 weeks (even up to years) are designated as a chronic condition. The cause is rarely identified.

Hives disappear once the body has completely reabsorbed the fluid back into the blood stream.

What your Doctor can do for you

Urticaria is not a disease but a symptom of many possible causes. To determine its origin, a detailed clinical history and evaluation of the appearance and duration of the blotches is critical. The doctor may recommend skin tests to determine if it’s an allergy or not. Others include blood tests, or food or medication diaries.
Hives caused by allergies usually resolve naturally. But they may also be treated with antihistamines that prevent further appearance of symptoms. In severe cases, corticosteroids are used to bring down the inflammatory responses. A person may need a shot of epinephrine if the condition does not respond to treatment or is causing breathing difficulties already.

What you can do

Fluid that leaks into the epidermis irritates the nerve endings found in that area thereby causing an itch. Here are some ways to help ease the itchy sensation.

• Don’t scratch. As much as possible, avoid scratching as this can increase inflammation and worsen the itching.
• Cool compresses or ice packs over the site can improve localized urticaria. For generalized rashes, a cool colloidal bath (e.g. oatmeal, baking soda) will help soothe the itching.
• Avoid wearing tight fitting clothing or garments to decrease skin irritation.
• The most recommended treatment for urticaria is to take an over-the-counter antihistamine like diphenhydramine.
• If you know the cause of your hives, remember the golden rule in any allergic reaction—to avoid the trigger. These can include peanuts, nuts, eggs, beans, chocolate, corn, fish, antibiotics, nsaids, and many more. Consult your allergist for more details regarding allergy management.