L50-L54: Urticaria and erythema

L50: Urticaria

Urticaria, also known as hives, is a group of conditions that causes a skin rash characterized by itchy, raised bumps. These conditions can be caused by a variety of triggers, including allergies to certain foods or drugs, exposure to certain physical factors like heat or cold, or even stress. The inflammation, redness, and itching are caused by the release of histamine and other chemicals from immune cells in the skin. The rash can appear anywhere on the body and can vary in size, from a few millimeters to several centimeters. Urticaria's progress can be acute (lasting less than six weeks) or chronic (lasting six weeks or more). While urticaria itself is primarily a skin issue, in severe cases, part of a systemic allergic reaction, it can affect other systems, leading to symptoms like difficulty breathing or gastrointestinal discomfort.