Hives are raised red bumps (welts) or splotches on the skin. They are a type of swelling on the surface of your skin. They happen when your body has an allergic reaction to an allergen, a substance that’s harmless to most people. But can also occur in autoimmune conditions or systemic conditions, if hives last for a prolonged period of time. Hives may be itchy, or you might feel them burning or stinging. They can be as small as a pinprick or as big as a dinner plate. The medical name for hives is urticaria. Sometimes, the welts from hives join together to form larger areas called plaques. Hives tend to fade within 24 hours, although they may be noticeable for several days or longer.
Causes:
- Latex
- Pollen
- Scratching
- Exercise
- Dust mites
- Some chemicals
- High body temperature
- Pet dander from dogs, cats, horses, and so on
- Cockroaches and cockroach waste
- Some plants, including nettles, poison ivy, and poison oak
- Insect bites and stings
- Chronic illness, such as thyroid disease or lupus
- Sunlight exposure
- Water on the skin
Symptoms:
Swellings, known as wheals, appear as a rash on the skin. They are usually pink or red, with an oval or round shape. They can range from a few millimeters to several inches across. They can be extremely itchy, and they have a red flare around them.
The wheals usually occur in batches, frequently on the face or the extremities, including the arms, hands, fingers, legs, feet, and toes.
Welts normally disappear within 24 hours, but new ones may form. They can appear on just one part of the body, or on several parts.
Symptoms normally disappear within 24 hours, but sometimes another weal appears as the last one fades.
In some cases, hives can continue for several days. People with chronic hives can have symptoms for months or years.
Types of Urticaria:
Acute urticaria
Chronic urticaria
Angioedema
