Urticaria or hives as it is commonly called, is an itchy rash consisting of localized swellings of the skin that usually last for a few hours before fading away. Urticaria results from changes in the small blood vessels of the skin. Such changes are brought about by the release of substances in the body, the commonest of which is histamine. Acute urticaria, which can last from a few hours to as long as a week is usually caused by drugs, specific foods or a viral infection. Sometimes, no cause can be detected. Urticaria occurring almost daily for more than 6 weeks is called chronic urticarial. It can be spontaneous (no inciting factors) or inducible (triggered/aggravated by physical factors such as heat, pressure, cold, vibration, sweat and sunlight etc)
The wheals of urticaria may be white, pink or red. They can be of different shapes and sizes, and are itchy. Although the rash may persist for many weeks or months, individual lesions typically disappear within a day, and often last only a few hours. They occasionally leave bruising especially in children. The deeper swellings of angioedema occur most frequently on the eyelids, lips and sometimes in the mouth, but they may occur anywhere. They are not usually itchy, and tend to last a few days. The skin may feel tight and painful.
See your doctor if:
Various classes and doses of antihistamines are usually first line treatment to relief symptoms of urticaria. Avoidance of triggers/aggravating factors also help. Additional medications such as H2-antagonist, Montelukast, oral steroids may be used in more severe cases. Newer effective injectable biologic medication (omalizumab) is also available. Discuss with your doctor what treatment would suit you best.