Chronic Urticaria
Chronic urticaria
(Hives) is a condition where an itchy rash persists on and off for six weeks or more. The cause of the rash is often not clear. Many people also develop swelling of the lips, tongue or other areas of the body from time to time. The symptoms can often be eased with antihistamine tablets.
What is chronic urticaria?
Urticaria (sometimes called hives) is an itchy rash caused by tiny amounts of fluid that leak from blood vessels just under the skin surface.
Urticaria
is classed as:
Acute urticaria - if it develops suddenly and lasts less than six weeks. Most cases last 24-48 hours. About 1 in 6 people will have at least one bout of urticaria in their life. It can affect anyone at any age. Some people have recurring bouts of acute urticaria.
Chronic urticaria - if it persists long-term. Chronic means persistent or ongoing. In chronic urticaria a rash develops on most days for at least six weeks. This is uncommon. About 1 in 1,000 people develops chronic urticaria at some stage in their life. It is twice as common in women as in men. Some people have an urticarial rash on and off for months, or even years.
What does the rash of urticaria look like?
The rash can affect any area of skin. Small raised areas called weals develop on the skin. The weals look like mild blisters and are itchy. Each weal is white or red and is usually surrounded by a small red area of skin which is called a flare. The weals are commonly 1-2 cm across but can vary in size. There may be just a few but sometimes many develop over various parts of the body. Sometimes weals that are next to each other join together to form larger ones. The weals can be any shape but are often circular.
As a weal fades, the surrounding flare remains for a while. This makes the affected area of skin look blotchy and red. The blotches then fade gradually and the skin returns to normal. Each weal usually lasts less than 24 hours. However, as some fade away, others may appear. It can then seem as if the rash is moving around the body. The rash may clear completely only to return a few hours or days later.
Are there any other symptoms?
The appearance of the rash and the itch can cause distress.
A related condition called angio-oedema occurs from time to time in about half of people with
chronic urticaria. In this condition some fluid also leaks into deeper tissues under the skin, which causes the tissues to swell.
The swelling of angio-oedema can occur anywhere in the body but most commonly affects the eyelids, lips and genitals.
Sometimes the tongue and throat are affected and become swollen. The swelling sometimes becomes bad enough to cause difficulty breathing.
Symptoms of angio-oedema tend to last longer than urticarial weals. It may take up to three days for the swollen areas to subside and go.
A variation called vasculitic
urticaria
occurs in a small number of cases. In this condition the weals last for more than 24 hours, they are often painful, may become dark red, and may leave a red pigmented mark on the skin when the weal goes.