Hives, or urticaria, are a nasty affliction visible on the skin. Hives manifest as a rash consisting of blotches or localized swellings (wheals) of the skin. Hives are usually caused by an allergic reaction. The swelling is caused by distention of the skin capillaries and escape of serum and white cells into the skin and tissues.
As if that weren't bad enough, hives are usually extremely itchy, and may occur in a small area or cover virtually the entire body. Most commonly the sufferer has an allergic reaction to a food or a drug. Other less common causes of hives are injections, insect bites, pollen, or physical factors like cold, light, or heat. Usually crops of hives come and go, remaining at one site for several hours and then reappearing at another; commonly an acute attack subsides spontaneously in a week or two. Though that sounds like a long time to me, chronic cases of hives may last for substantially longer periods of time.
Antihistamines and cortisone are considered helpful by western medicine for relieving the itching and reducing the swelling. For a more holistic treatment, try the freeze-dried extract of the stinging nettle (Urtica dioica) leaves, sold in capsules, or quercetin, a bioflavonoid obtained from buckwheat and citrus fruits. Pure quercetin powder is yellow, insoluble in water, and messy to take. It is easier to use in the form of a coated tablet.
Webster 1913 says that hives are the croup, but this is not correct.