Hives are small, itchy, red swellings on the skin. The swelling occurs singularly or in clusters. Hives tend to fade after a few hours, but new ones can appear. Most cases go away within a few days. But, some last a few weeks or longer.
Hives are often caused when the body releases a chemical called histamine. Histamine is released during an allergic reaction. Many people, though, get hives without being exposed to something they are allergic to.
While the cause is unknown in some cases, these factors may cause hives:
A risk factor is something that increases your chance of getting hives.
Tell your doctor if you have any of these:
Exposure to an allergen (something that causes an allergic reaction)
Exposure to an allergen that triggered hives in the past
Symptoms of hives can vary from mild to severe:
Excessive swelling of the eyelids, lips, or genitals
Difficulty breathing or swallowing—Call 911 if you are having these symptoms
The doctor will ask about your symptoms and medical history, and perform a physical exam. You may need to see a doctor who specializes in skin disorders (dermatologist) or allergies (allergist). The following tests will be done:
Skin prick test
—a tiny bit of an allergen is placed in your skin with a needle to see if the area becomes raised or irritated
—a small portion of abnormal skin is removed
—a test that uses radiation to take a picture of structures inside the body, especially bones
The best way to treat hives is to find and then avoid the cause.
If the cause can't be found, there are medications to treat hives:
Please be aware that this information is provided to supplement the care
provided by your physician. It is neither intended nor implied to be a
substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER
IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the
advice of your physician or other qualified health provider prior to
starting any new treatment or with any questions you may have regarding a