Urticaria is the medical term for hives, a condition also sometimes called welts or nettle rash.
This skin condition is characterized by a raised, red, irritable rash that is itchy, and can range from being a few millimetres in size to the size of a hand. Hives can be localized (affecting one area of the body) or it could span large areas.
Acute urticaria occurs when the rash clears within six weeks of developing, while the term chronic urticarial is used to describe cases in which the rash persists for six weeks or longer. This is rare however, as most cases will dissipate of their own accord within 24 to 48 hours.
What causes Urticaria?
High levels of histamine in the skin lead to the onset of urticaria, although the exact triggers of this histamine release are largely unknown.
Histamine are chemicals created by the immune system, and are developed to combat allergies in the body. When histamine and other chemicals under the skin’s surface layers (epidermis) are released, the tissues can swell and become inflamed, bursting the blood vessels thus creating the reddish-pink tone of the rash. Things such as allergic reactions, infections, antibiotics, and stress are often found to be the case of short-term hives, while chronic urticaria may be caused by an autoimmune condition by which the body mistakenly attacks it’s own tissue.
What are the symptoms of Urticaria?
Symptoms of hives include red rashes and white welts that appear in batches across the body.
These can appear on the face, arms and legs, and torso, and vary in size and shape. The rashes may swell and itch depending on the severity, and this swelling may in turn cause pain or burning to develop depending on the location of the welts. Consuming alcohol or caffeine, along with exposure to warm temperatures and high levels of stress can worsen the symptoms of hives. For this reason, people suffering from hives may wish to avoid activities such as exercise until the rash has healed and the itching subsided.
Images of Urticaria
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How do Dermatologists diagnose Urticaria?
A Dermatologist will diagnose urticaria by examining your skin and taking a medical history. They may recommend a skin biopsy, allergy testing or bloods tests in order to rule out any underlying health issues or infections
How do you treat Urticaria?
It the majority of cases, seeking hives treatment is not necessary, as the condition will heal on it’s own within a few days.
In many cases however, the itching can cause discomfort, and in these cases taking antihistamines or applying a topical cream can help provide relief. In more severe cases, your GP may prescribe a course of steroids to treat the rash, while persistent chronic cases may warrant referral to a dermatologist.