Hives / Utricaria

About

Hives are allergic skin reactions that appear suddenly in clusters or single bumps or blotches (swelling) on the skin surface and can be itchy. Hives is medically known as Urticaria (pronounces as ur-tuh-kar-ee-uh). These occur due to allergy to food substances (e.g strawberry, shellfish, prawn, milk, nuts and choclates) or drugs (e.g sulpha or penicillin) or sometimes due to no known cause.

Hives may be small in size like a button and may at first look like mosquito bites. Alternatively, the large blotches maybe several centimeters in diameter. Very often the smaller ones join together and form a large raised red patch and this is then called a plaque. The rash can be itchy or the involved area can cause a constant burning or stinging sensation.

These rashes are mostly red or pink in color with a pale center and circular in shape and usually are commonly seen to occur on the arms, trunk and legs. If the welts or the swelling occurs around the face particularly in the eyes, lips and (sometimes) throat, it is called angioedema.

Most people will get anxious and visit a doctor immediately as it appears in such a dramatic fashion.

Hives can last for a few hours or take several days to fade away and disappear spontaneously. Usually these are benign lesion but can be life threatening angioedema if it involves the inside of the throat, tongue and windpipe. Ten to 25% of the general population will experience Hives at least once during their lifetime.

Our immune system is designed to fight - fight foreign substances particularly disease- causing bacteria and viruses that the ‘surveillance’ system considers as threatening. When the immune system over-responds, allergy results. The antibody- IgE- that plays a key role in allergic response in produced in excess in some people particularly in those who are familiarly predisposed.

Sometimes allergy occurs when the body is hypersensitive to some particles known as allergens. During an allergic reaction, chemicals (Histamine) are released that cause the swelling on the skin that is characteristic of hives. Common allergens include animal dander, dust mites, food substances, pollens, molds, medicines, industrial chemicals, and insect venom.

Hives are a common in occurrence especially in individuals who already suffer from other allergies, such as hay fever. It is not contagious.