Hives are pink or red bumps on the skin. These bumps are also known as wheals. The bumps can itch, burn, or sting. Hives can occur anywhere on the body. They vary in size and shape and can form in clusters. Individual hives can appear and go away quickly. New hives may develop as old ones fade. Hives are common and usually harmless. They are not contagious. Occasionally, hives are a sign of a serious allergy.
Hives may be caused by an allergic reaction. They may occur from:
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Certain foods, such as shellfish, nuts, tomatoes, or berries
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Contact with something in the environment, such as pollens, animals, or mold
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Certain medicines
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Sun or cold air
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Viral infections, such as a cold or the flu
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Bacterial infection, such as strep throat
If the hives continue to come and go over many weeks without any other symptoms (chronic hives), the cause may be very hard to figure out.
You may be prescribed medicines to ease swelling and itching. Follow all instructions when using these medicines. The hives will usually fade in a few days. But they can last for weeks or months.
Home care
Follow these tips:
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Try to find the cause of the hives and eliminate it. Discuss possible causes with your healthcare provider. Your healthcare provider may ask you to keep track of the food you eat and your lifestyle to help find the cause of the hives.
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Don’t scratch the hives. Scratching will delay healing. To reduce itching, apply cool, wet compresses to the skin.
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Dress in soft, loose cotton clothing.
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Don’t bathe in hot water. This can make the itching worse.
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Apply an ice pack or cool pack wrapped in a thin towel to your skin. This will help reduce redness and itching. But if your hives were caused by exposure to cold, then do not apply more cold to them.
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You may use over-the counter antihistamines to reduce itching. Some older antihistamines, such as diphenhydramine and chlorpheniramine, are inexpensive. But they need to be taken often and may make you sleepy. They are best used at bedtime. Don’t use diphenhydramine if you have glaucoma or have trouble urinating because of an enlarged prostate. Newer antihistamines, such as loratadine, cetirizine, levocetirizine, and fexofenadine, are generally more expensive. But they tend to have fewer side effects. They can be taken less often.
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Another type of antihistamine is used to treat heartburn. This type includes nizatidine, famotidine, and cimetidine. These are sometimes used along with the above antihistamines if a single medicine is not working.
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If the hives are severe and you do not respond well to other medicines, you may be given a steroid, such as prednisone, to take for a short time. Follow all instructions carefully when taking this medicine. Tell your healthcare provider about any side effects.
Follow-up care
Follow up with your healthcare provider if your symptoms don't get better in 2 days. Ask your provider about allergy testing if you have had a severe reaction or have had several episodes of hives. Allergy testing may help figure out what you are allergic to. You may need blood tests, a urine test, or skin tests.
When to get medical advice
Call your healthcare provider right away if any of these occur:
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Fever of 100.4°F (38.0°C) or higher, or as advised
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Redness, swelling, or pain
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Bad-smelling fluid coming from the rash
Call 911
Call 911 if any of the following occur:
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Swelling of the face, throat, or tongue
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Trouble breathing or swallowing
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Dizziness, weakness, or fainting
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Coughing that won't stop
Author: Wheeler, Brooke
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