Urticaria is a very common response pattern of the skin, which is characterized by wheals, and can be triggered by various internal and external stimuli. Allergies or intolerances to foods and drugs, physical stimulation of the skin through heat, cold, light, pressure or water, as well as mental stress may be a trigger for urticaria. Sometimes the cause can not be determined with certainty. This form of idiopathic urticaria often occurs suddenly and usually lasts one to three years.
People affected with nettle rash first form pale red to darker red elevations of the skin, similar to mosquito bites. However, these are growing rapidly, forming so-called wheals. They itch very strongly - similar to the response after coming in contact with stinging nettles, hence the name nettle rash.
Wheals are edematous elevations of the dermis of bright red color (urticaria rubra), which in severe edema can appear pale-white (porcellanea urticaria). Cause of the swelling usually is the neurotransmitter histamine, which increases the permeability of the dermal blood vessels and thus causes water retention in the dermis. In addition to an increased release of histamine from mast cells it can also be caused by a disorder preventing the decomposition of histamine. In rare cases, urticaria can also occur in the course of an autoimmune disease (hereditary angioedema).
Chronic urticaria can have organic causes, such as disorders of the adrenal cortex or hidden inflammation in the body.Recently, doctors suspect that Helicobacter pylori, a bacterium found in the stomach, may be a cause of the hives.Another trigger is stress.
Therapy:Often wheals disappear all by themselves, usually as quickly as they appeared. Then no treatment is necessary.However, if the patient shows signs of chronic urticaria, which means symptoms persist more than 4-6 weeks, the physician can administer antihistamines, or cortisone. Some antihistamines are also freely available in pharmacies. However, this treatment only causes a suppression of symptoms. Persisting chronic hives may require a multi-day hospital stay in the search for the triggers.If antihistamines and cortisone show little to no disease modifying effects it may be a psychosomatic cause. Here rapid stress reduction and psychotherapy may be advisable.
