Urticarial rash, or hives, is a skin condition characterised by raised, itchy welts of varying sizes that can appear anywhere on the body. These welts often present as red or skin-coloured and may blend into each other, forming larger areas of swelling. Urticarial rash can range from mild to severe, and although it is typically not life-threatening, it can still significantly affect your quality of life. The condition is caused by the release of histamine and other chemicals into the skin, typically as part of the immune system’s protective response. When triggered, this reaction causes blood vessels to expand and leak fluid, leading to the swollen, raised patches associated with hives. The rash itself can last from a few hours to several days; in cases of chronic urticaria, it might even persist for six weeks or longer.