
Urticaria
- usually transient vascular reaction involving the upper dermis, representing local edema caused by dilation and increased permeability of the capilliaries and the development of wheals.
- Urticaria.
- An itchy skin eruption characterized by weals with pale interiors and well-defined red margins; usually the result of an allergic response to insect bites or food or drugs.

Allergic urticaria

Idiopathic urticaria

Urticaria due to cold and heat

Dermatographic urticaria

Vibratory urticaria

Cholinergic urticaria

Other specified urticaria

Unspecified urticaria
- usually transient vascular reaction involving the upper dermis, representing local edema caused by dilation and increased permeability of the capilliaries and the development of wheals.
- Urticaria.
- An itchy skin eruption characterized by weals with pale interiors and well-defined red margins; usually the result of an allergic response to insect bites or food or drugs.