Pressure urticaria

A common type of hives (urticaria) that occurs after the skin has been under pressure, often the feet after standing or the buttocks after sitting for a long time or areas where clothing is tight.

The hives are typically deep and invisible to the eye.

The hives may begin hours after the pressure on the skin has ceased.

The hives last 8 to 72 hours and may be painful, itchy, or burning.

They may be accompanied by low fever, chills, fatigue, joint and muscle aches, and/or headaches.

Triggers include pressure from using tools (such as a screwdriver or a hammer), clapping the hands, carrying a bag or suitcase, sexual intercourse, and the use of tampons.

Aspirin is known to be a trigger.

Antihistamines may not help.

Nonsteroidal anti-inflammatory drugs (NSAIDs) or oral steroids may be used.

The disease tends to be chronic and last for years.

The cause is unknown