Urticaria (hives) is basically an allergic skin rash that 15% of the world population will have experienced at some point in their lives. In most cases, the hives go away within a few weeks or less; however sometimes they may turn into a chronic problem. And a whopping 80% of the chronic cases are idiopathic, which means that no cause can be found.
The typical description of Urticaria is an itchy skin eruption that is characterized by 'wheals'. The wheals usually have with well-defined red margins and pale interiors. As discussed earlier, Urticaria is a manifestation of an allergic reaction and the eruptions tend to come and go intermittently. The wheals can last for several hours or even the whole day before fading off. When the wheals disappear, they do so without any trace.
Urticaria rashes can occur anywhere on the body such as the trunk, arms, legs, face, etc. They have a tendency to change locations - disappearing from one place and reappearing in another often in a matter of hours. A severe variant of Urticaria, called Angioedema is marked by swelling that occurs beneath the skin (at a deeper level) and this can be life-threatening.
The cases may be acute in nature (lasting less than 6 weeks) or may run a chronic course (for more than 6 weeks). In either case, treatment must be sought early on, so as to treat it effectively in the early stages itself.