Urticaria also called nettle-rash or hives or wheals in a common language, simply means itching with rash and mainly effects the neck, arms, legs and trunk of the children. Medically, urticaria may be defined as skin eruption , which is allergic in origin and is characterized by profound itching, red circular or irregularly shaped eruptions on any part of the body.
These eruptions can remain on the body for variable period, anywhere between few seconds to even hours. They have tendency to disappear and reappear. They tend to disappear without leaving behind any trace.
Urticaria is an allergic skin disorder . Characteristically the skin eruptions are erythematous, raised above the skin level, with intense itching and usually worsened by itching & with slight local warmth.
Some causes of urticaria are given below-
Common causes of urticaria are infections, foods, drugs and physical
agents (e.g. heat, sweating, exercise, sunlight, pressure, cold).
Occasionally, insect bites and internal disease may also be responsible.
Sometimes, no cause can be found.
Common foods that cause urticaria include nuts, eggs, fresh citrus fruits,
tomatoes and shellfish. Food additives and preservations such as
tartrazine (yellow dye) may also be responsible .
Many infections can cause urticaria. Viral upper respiratory infections are a
common cause, especially in children. A number of bacterial and fungal
infections can also cause hives.
Drugs that commonly produce urticaria include antibiotics (e.g. penicillins,
sulphonamides), pain medications (e.g. aspirin, codeine), sedatives and
diuretics. It is important to realize that virtually any medicine can cause
hives. Thus, over the counter medications such as vitamins, antacids, eye
and ear-drops, laxatives are potential causes of urticaria. It is important
for your doctor to be aware of all these preparations that you use.
In this disease the blotchy rash consists of a number of pale raised bumps or wheals surrounded by reddened skin. The rash is extremely itchy and debilitating. Lesions tend to move about every 24 hours and “migrate” around on the body. They may, however, clear up in one area only to appear in another. This pattern can continue for as long as the allergen remains. When larger areas of the skin are involved, the condition is called angioedema, and may include severe swelling that interferes with breathing.
The outbreak of urticaria is sudden and the disease may affect any part or the entire body. The eruptions may be as small as pin heads or as large as a rupee.
Antihistamines are the mainstay of treatment, and most patients need no other treatment. It is very important that you should have an antihistamine which is appropriate for you. We are talking here about the sort of antihistamine usually used for allergies, even though chronic urticaria is rarely if ever caused by true allergies. This type of antihistamine is called an ‘H1 blocker’. These commonly used antihistamines are two main kinds.
Identification and then elimination of the factors inducing urticaria is an important measure, whenever possible. Improved environment, corrected food habits, etc. help whenever applicable. Treatment of the other disease where Urticaria is secondary to the underlying disease condition is an important step.