Urticaria, also known as hives, is a outbreak of swollen, pale red bumps or plaques (wheals) on the skin that appear suddenly — either as a result of the body’s reaction to certain allergens, or for unknown reasons. Hives usually cause itching, but may also burn or sting. Hives may sometimes be associated with swelling of the face and lips.

Treatment includes oral anti-allergic medicines. The challenge lies in recognizing the allergen