A subset of chronic hives is known as physical urticaria. This means that a specific physical stimulus causes hives in certain people. Physical hives cause up to 16% of chronic hives. A general description of each type of physical hives is given here, and a more detailed description is given separately.
Dermographism - Hives are produced suddenly by rubbing or stroking the skin. This type of physical hives is very common.
Pressure Urticaria - Hives are produced several hours after applying pressure to the skin. This is a fairly common form of hives and difficult to diagnose since the hives develop hours after contact with the skin.
Cholinergic Urticaria - Hives are produced during or shortly after exercise. This is a very common type of hives.
Exercise Induced Anaphylaxis - People with this disorder develop hives, shortness of breath, and dizziness after exercising. Some people with this condition may pass out or go into shock. This condition is very rare and was only first described in 1980.
Cold Urticaria - Hives are produced with a sudden drop of temperature or exposure to cold water or ice. This is a frequent cause of hives.
Solar Urticaria - Hives occur minutes after exposure to the sun and disappear within 1 hour. This is a fairly frequent cause of hives.
Heat Urticaria - Hives occur within minutes after exposure of the skin to a warm stimulus. This type of hives is very rare.
Vibratory Angioedema - Angioedema is produced after exposure of the skin to vibration. This is also a very rare type of hives.
Aquagenic Urticaria - Hives are produced immediately after exposure of the skin to water. This form of hives is also very rare.
