Pressure urticaria is a rare form of hives that arises once excessive or continuous pressure is applied on the skin. This includes weight from friction, carrying a heavy load or vibration.
Even though a pressure rash might arise right after placement of pressure, it often arises 4-6 hours after the pressure was removed. The usual site of the rash includes the feet, hands, trunk, legs and buttocks.
It is a chronic condition that starts during the 20s and 30s and can persist for several years before resolving. Even though it is not detrimental to overall health, it can be uncomfortable and disrupt with quality of life and sleep.
What are the causes?
Even though the precise mechanism why pressure urticaria develops is unknown, it is believed to be an autoimmune condition where the immune system responds to the pressure in the same way as an infection where immunoglobulin E are released into the bloodstream.
It can be worsened by heart, menstruation, aspirin or often experienced by individuals with autoimmune ailments such as lupus, rheumatoid arthritis or autoimmune thyroid disease.
What are the signs?
Pressure urticaria is defined by elevated, reddened wheals that can be itchy, warm and minimally painful. They tend to feel dense and deeper than the other types of urticaria and might take up to 72 hours to settle. It might also be accompanied by headache, fever, chills, fatigue and body aches.
In most cases, it is limited to the affected part of skin. It can be triggered by wearing constricting clothes, standing on one’s feet for an extended period, sitting in one place or leaning against hard surfaces. In some cases, it might form under a shoulder strap or belt that is too tight.
Management of pressure urticaria
At the present, there is no available measures to prevent or completely avoid pressure urticaria.
Even though oral antihistamines are generally given, their effectiveness tend to vary from one individual to another. Some topical corticosteroids might be useful in lowering the inflammation but only given for a brief period due to the risk of skin thinning especially in high strengths.
Non-steroidal anti-inflammatory drugs (NSAIDs) might be prescribed by the doctor if the swelling is accompanied by pain. The newer-generation asthma drugs might be given to provide relief in some cases.