Urticaria Causes

Urticaria or hives is a type of skin rash that appears as a raised, red bump on the surface of the skin. This type of skin rash can develop in any part of the body, and can last for several hours to weeks. Most commonly, urticaria is caused by allergies, though factors other than just allergic reaction to certain substances too can cause urticaria or hives, especially the chronic one. The hives are usually formed when histamine is released by the mast cells. Histamine is the chemical responsible for causing allergic reactions. It basically dilates the blood vessels, and causes fluid leakage from the superficial blood vessels. This is turn leads to swelling or the appearance of raised bumps that last until the interstitial fluid is absorbed by the surrounding tissues.

What Causes Urticaria?

There are mainly four types of urticaria, and each of them has certain specific triggering factors. As for example, acute urticaria is usually a result of allergic reactions, which can be triggered by a number of factors including, insect bites and consumption of certain foods like, shellfish, eggs, nuts, wheat, milk, berries and soy products. Sometimes, non-allergic factors such as infections, caused by bacteria, virus and fungus can also cause urticaria. So, many times, urticaria can be caused by viral upper-respiratory tract infections, viral hepatitis, fungal infections, as well as streptococcus and H. pylori infections.

Chronic urticaria on the other hand, can be idiopathic, as no specific cause has been found for this condition. However, autoimmune diseases are usually considered as the possible culprit behind the onset of chronic urticaria. The hives developed due to chronic urticaria can persist for more than 6 weeks. Another type of urticaria, known as drug induced urticaria can develop as a part of the reaction to a particular medicine. Such medicine can anything including, antibiotics, aspirin, non-steroidal anti-inflammatory drugs and pain killers. Dermatographism or dermatographic urticaria often develops, after scratching or stroking the skin. Physical urticaria can be caused by an exposure to sunlight, cold, heat, friction and pressure.

So, an exposure to cold can cause the appearance of cold urticaria, while solar urticaria usually appears after sun exposure. Hives can also develop in the parts of the body, where the skin has been under pressure for a long time. Therefore, prolonged standing or sitting, along with wearing tight-fitting clothes can be reason for the development of pressure urticaria, that can more commonly appear in areas like, the feet and the buttock. Apart from these, one can get hives or urticaria due to dietary histamine poisoning, which can occur as a result of ingestion of free histamine, released by bacterial decay of fish flesh. Certain food additives and preservatives can also be some important causes of urticaria.

Urticaria Symptoms

Urticaria is characterized by raised bumps or wheals, surrounded by a red margin or border. Such bumps or hives are often accompanied by itching and a burning sensation. This type of skin rash can enlarge and spread to other areas. Such skin lesions or eruptions can be very small, just the size of a pin head, and as large as the size of a coin. They often clear up within a couple of hours. However, hives caused by chronic urticaria can last for 6 or more weeks.

Urticaria Treatment

Urticaria is most often managed with the help of antihistamines drugs. However, appropriate treatment to a great extent depends on the type of urticaria, as well as its severity. At times, physicians combine antihistamines with other drugs to control or alleviate the symptoms of urticaria. Severe cases might require the administration of steroids, tricyclic medications, immunosuppressant drugs and epinephrine injections. However, proper management of the condition would require the identification of the underlying factors that trigger the development of hives.

Identifying the specific cause behind this condition for each individual can be quite hard. But still, effective management of this condition is possible only with the identification and removal of the actual triggering factors. Only a physician can help to ascertain the underlying causes. Therefore, it is imperative to talk to your physician, if you get hives frequently and the condition looks quite alarming.