Hives are raised, red patches of skin that are extremely itchy.
The medical term for hives is urticaria. They are often referred to as "welts" on the skin, and they can vary in size greatly or even connect to form larger welts. The hives themselves are fleeting, with individual hives resolving in less than 24 hours. However, as an older one fades, a newer one will often form in a nearby place, so the overall hives can last several weeks. If hives last longer than 6 weeks, they are referred to as chronic.
Hives appear as raised bumps on the skin that are most often red but sometimes skin-colored. They will "blanch" or turn white in the center when pressed. They can appear on any area of the body, change shape, move around, disappear, and reappear over short periods of time. They appear suddenly and will often go away just as quickly.
Hives can occasionally be associated with a condition called "angioedema" which is a condition that is characterized by puffiness or swelling on the face, eyelids, ears, mouth, hands, or feet. These two conditions can sometimes be confused with an allergic reaction. Signs of a dangerous reaction include: trouble breathing, tightness in the throat or difficulty swallowing, nausea and vomiting, and cramps or stomach pain. You should see a doctor right away if you have any of these symptoms associated with your hives.
Acute hives can often be caused by certain triggers that are known to cause hives commonly. Chronic hives, those lasting longer than six weeks, often do not have a known trigger or allergy. If a trigger is found, avoiding the trigger is the mainstay of treatment. Otherwise, a dermatologist can evaluate you to help determine the underlying cause of your hives and to help find the right treatment regimen for you.
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