Urticaria  is a skin reaction that causes itchy welts. Chronic hives are welts that last for more than six weeks and return often over months or years. Often, the cause of chronic hives isn't clear.  The welts often start as itchy patches that turn into swollen welts that vary in size. These welts appear and fade at random as the reaction runs its course.

SYMPTOMS

• Batches of welts (wheals) that can arise anywhere on the body
• Welts that might be red, purple or skin-colored, depending on your skin color
• Welts that vary in size, change shape, and appear and fade repeatedly
• Itchiness (pruritus), which can be intense
• Painful swelling (angioedema) around the eyes, cheeks or lips
• Flares triggered by heat, exercise or stress
• Symptoms that persist for more than six weeks and recur often and anytime, sometimes for months or years