Urticaria commonly known as hives, weals, welts or nettle rash is an allergic condition where the skin appears to be itchy with rashes. It may appear to a definite part of the body or spread across a larger area.

The disease affects 20% of people at some time in their lives. Urticaria is not a contagious disease. Whenever an allergic reaction occurs, the body releases a protein called histamine. When histamine is released into the blood, the tiny capillaries (blood vessels) leak the fluid. This fluid accumulates in the skin results in causing rashes.

In some rare cases, Urticaria is also known as vasculitis, which causes the blood vessel to be inflamed. In these cases, the rashes persist more than 24hrs, they are more painful and most of the time leave bruises.