Urticaria: Causes, Triggers, and Treatment

What is Urticaria (hives)?

Urticaria, also known as hives, is characterised by itchy raised bumps (weals) that are reddish or skin coloured lasting from a few minutes to a few hours.  They usually appear suddenly and fade away within 48 hours.  Urticaria does not leave scars on the skin.  Urticaria is a common skin condition.  About 20 % of people will have hives sometime during their lives.  In most people, hives go away within a few hours to a few days, and even up to a week. This is called acute urticaria.  For some people, the hives may last more than 3 to 6 weeks, even continuing for many years.  This is called chronic urticaria.  Hives are generally harmless, but require immediate medical attention if there is throat swelling.

What causes hives?

Hives are produced by fluid leaking through small blood vessels in the skin.  This leakage of fluid is caused by the opening of tiny gaps in the cells lining the small blood vessels, as a result of a natural chemical called histamine.  Histamine is released in response to inflammatory reactions.  The inflammatory reactions can be caused by infections, foods, drugs, physical insults (e.g. heat, cold, exercise, pressure) or rarely, internal diseases.

Sometimes, the cause for hives is unknown.

Common foods that cause hives include eggs, peanuts, fresh citrus fruits, chocolate, fish and pork.  Food preservatives like tartrazine (yellow dye) or monosodium glutamate (MSG) may be responsible.

Essentially any drugs (including over-the-counter medication) can cause hives.  The common culprit drugs include antibiotics (e.g. penicillin, tetracycline), pain medicines (e.g. aspirin, codeine), sedatives and diuretics.  It is important, therefore, to inform your doctor of all the medications that you are taking.  Infections causing hives include the common cold or certain bacterial and fungal infections.

Urticaria triggers

A consultation at Pymble Dermatology will ascertain the triggers that are causing hive outbreaks. Your practitioner can then suggest treatment pathways or prescribe medications to combat more severe cases. Your allergist will explore potential triggers such as family disease history, exposure to substances, current medications and ongoing food allergies. In some cases, skin, blood or urine tests are helpful in evaluating the triggers that cause urticaria.

Treatment of urticaria

The best treatment for hives is to know the cause and to avoid or remove it.  While investigating the cause, your doctor will prescribe you with anti-histamines to block the reaction.  Non-sedative anti-histamines are prescribed in the day.  Sometimes sedative anti-histamines give a more complete relief at night.  Take the anti-histamines as directed by the doctor.  In addition, persons with Urticaria are advised to avoid the heat, sun and hot shower.  Do not scrub the skin. Alcohol can make hives worse.

Clinical experts at Pymble Dermatology are experienced in ascertaining the cause of hives. The physician will ask targeted questions related to your personal experience of the condition and explore possible connections associated with past medical episodes. Skin tests and blood tests can also be undertaken to ascertain any system-wide condition that is causing urticaria outbreaks. With professional medical help and guidance, the effects and degree of urticaria can be greatly minimised or eliminated entirely.