Urticaria is an illness which can be very discouraging. It is estimated that about 20% of all people have experienced urticaria in their lifetime. Most incidences of urticaria are acute, with symptoms lasting anywhere from a few hours to a few days. Only rarely will the condition persist for longer than six weeks. If symptoms do continue past six weeks it is considered to be chronic urticaria. The wheals that arise on the body with urticaria often appear in one particular area. Then after a short period of time they may disappear only to be followed by eruptions on other areas of the body.