What Is Hives, Why Does It Occur, and Does It Need Treatment
Usually, hives are a short-term condition and go away on their own after the trigger that caused them is removed. But if they persist for a long time and do not respond to standard treatment, special medications are used, in particular Dexamethasone.
Types of hives
The rash may be localized in one area or spread throughout the body, covering the skin with welts of different sizes — from 1–2 mm to several centimeters. Doctors distinguish two main forms of urticaria:
- Acute — if the rash disappears completely within six weeks (in most cases, it lasts from 24 to 48 hours).
- Chronic — when the rash persists or appears and disappears for more than six weeks, with recurrences over many years.
A rare type of hives, known as urticarial vasculitis, causes inflammation of the blood vessels within the skin. In this case, the swellings or welts last longer than 24 hours, are more painful, and may leave a bruise.
When to seek medical help
Causes of hives
The appearance of an itchy rash and welts is linked to a process in which a trigger causes the release of large amounts of histamine and other chemical mediators in the skin. It is this extra fluid in the tissues that leads to swelling and itching. The release of histamine may be caused by:
- an allergic reaction, such as a food allergy or a reaction to an insect bite;
- exposure to cold or heat;
- an infection, such as a viral one;
- certain medicines that cause hives as a side effect.
In many cases, no obvious cause can be identified. But prolonged hives are often triggered by the immune system mistakenly attacking healthy tissues. That is why they are difficult to treat and require additional examinations. A number of triggers can also make symptoms worse: alcohol or caffeine consumption, emotional stress, and a warm surrounding environment.
Treatment
In most cases, hives do not require treatment if the symptoms are mild and go away within a few days. When the itching causes discomfort, over-the-counter antihistamines are prescribed. A doctor may consider a short course of steroid tablets (oral corticosteroids) for more severe cases of urticaria.
