What Causes Hives?

Over 50% Of Sufferers Don’t Know, Our Poll Show

Fifty-four percent of people who have had a hives outbreak don’t know what caused it, according to a poll done by BeeHealthee.com. Hives, also called urticaria, affect about 20% of the population in the US, most commonly people aged 20 to 30. Most health experts believe that the root cause of hives is an allergic response to a food or drug, but according to our poll, the trigger is often never found.

Sixteen percent of those polled on BeeHealthee.com stated stress was the known cause of their hives, followed by a reaction to medication (13%), an allergic reaction to food (10%), an infection (6%) and an insect bite or sting (1%).

Most cases of acute hives simply resolve themselves on their own after treatment with antihistamines, which block the release of histamine from the cells. In very rare cases, an allergic reaction can cause anaphylaxis, which can be life-threatening.

Types of Hives

There are two types of hives: acute and chronic. Acute hives last for less than 6 weeks, while chronic hives persist for longer than 6 weeks. Over-the-counter antihistamines are effective for hives, but they often have the side effects of drowsiness or sedation in patients. Newer prescription antihistamines are often preferable, as they do not cause these side effects.

Hives Symptoms

Hives present as swellings on the body that often cause itching. They may be pink or red, or appear skin-colored. Hives occur when the cells in the skin release histamine, a chemical that causes the blood vessels in the skin to leak fluid. When this leaked fluid accumulates in the skin, it swells and forms hives.

Hives Causes

Hives can be caused by numerous factors: a sudden increase in heat or cold, sunlight, exercise, pressure from an object, stress, chemicals, cosmetics or soaps. They may also be the result of an allergic reaction to something that was inhaled such as pet dander or pollens, from an insect sting, or from a food such as dairy products, fish or shellfish, or nuts. In some cases, hives may be caused by an over the counter medication like aspirin, or a prescribed medication like penicillin. Hives can occur after an infection, or may be associated with types of conditions like thyroid disease or with yeast present in the body (Candida albicans).

Hives Diagnosis

Acute hives are less complicated to diagnose than chronic hives. First, the physician will take a detailed history, ask the patient to keep a food diary, and document all medications and time the hives started. Skin testing may also be beneficial to determine if an allergen, infection or medication caused the hives to appear.