Overview of Hives
There are many varieties of hives. They may have a variable appearance, generally are red in color, often round and raised, and are of varying sizes. The hallmark symptom in most patients is itchiness. A mild case of hives often disappears on its own after a few hours, but may last or occur on and off for weeks, months and even years.
Acute hives that last less than 6 weeks are generally caused by a variety of allergens that may include foods, insect stings, bites and infection (particularly in children). A medication a patient takes such as aspirin, non-steroidal anti-inflammatory drugs such as ibuprofen or antibiotics can be some of the leading causes. Please also note that acute hives may be part of an allergic reaction that can be associated with life-threatening symptoms.
When hives last for more than 6 weeks they are known as ‘chronic’. About 1% of the US population suffers from chronic hives, and in many cases it is extremely difficult to determine the exact cause.
Chronic hives are generally more common in middle-aged adults and women. The immune system may be somehow involved, especially in cases where an answer is elusive. Other common causes associated with chronic hives include thyroid and hormonal conditions as well as physical triggers like rubbing, scratching, vibration, water, skin pressure and even changes in skin temperature.
Solar or Light Triggered Hives
In some cases, such as solar or light triggered hives, a simple sun block and avoidance will provide the answer. With delayed pressure hives, the symptoms may be slow to start but last longer periods of time. Loose-fitting clothing may help in this case. Dressing warmer can reduce cold temperature hives, especially if you wear gloves.
In many cases, it may be difficult to know the exact cause of a hive. In allergic associated hives, there may be a pattern of exposure (cause and effect) and keeping a food diary can often provide some valuable insight into possible triggers. In a small number of individuals with hives, exercise actually can be the provoking stimulus.
Some of the most effective and safest treatment of hives can come from second-generation, non-sedating oral antihistamines. These medications will reduce itchiness, the size of the hive and the frequency and severity of the episodes. In some cases when hives are severe and /or persistent oral steroids may need to be prescribed to control the itchiness and/or swelling of the skin.
In many cases you may need to see your health care provider or a specialist, such as a dermatologist or an allergist.
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