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Hives are a raised, itchy, red rash caused by tiny amounts of fluid that leaks from the blood vessels just under the skin’s surface. It may appear on one part of the body and be just a few millimetres in size, or be spread across larger areas.  

There’s two main categories of hives: 

  • Acute urticaria: Where the rash clears completely, usually within a six-week window.
  • Chronic urticaria: In some rare cases, a rash may continue over a longer period of time. This can last anywhere from over six weeks to multiple years.

It’s estimated that one in five people will be affected by acute urticaria at some point in their lives, whereas chronic urticaria will only affect about one in 100.

Acute urticaria can be triggered by allergens, irritants, infections, medicines or physical factors like heat or exercise.

High levels of histamine and other chemical messengers released in the skin cause the blood vessels in the affected area to open up and leak. This extra fluid causes itching, swelling and a red/pink colour.

Chronic urticaria, however, is linked to other conditions, such as autoimmune problems. With chronic urticaria, the immune system is mistakenly attacking healthy tissue.

Sometimes no obvious cause can be located, however, there are certain triggers that make symptoms worse that include:

  • Drinking alcohol or caffeine
  • Emotional stress
  • Increasing body temperature

The condition consists of spots or patches of raised red or white skin, which usually clear away in a few hours and are then replaced by fresh patches. It typically occurs with swelling in other areas of the body (usually the hands and feet) and will be itchy, painful or cause a burning sensation.

Most cases will involve symptoms being present for around eight to 12 hours and these will rarely continue for more than 24 hours. In rarer cases, problems will continue for quite a few days, and even several months.

Urticaria has a tendency to flare up because of triggers, such as heat, exercise and stress. Symptoms may also reoccur frequently, unpredictably, and will sometimes last for months or years.

You should seek emergency care if you have any of the following symptoms, since these can indicate the presence of a more serious condition:

Feeling of dizziness
Severe chest tightness or trouble breathing
Feeling your tongue or throat swelling

Acute urticaria: This won’t usually require treatment due to the condition being mild and relatively short-lived. If the condition persists or slightly worsens, antihistamines/corticosteroids may be prescribed to manage symptoms.

Chronic urticaria: For those suffering from long-term bouts of hives, medication may be prescribed such as antihistamines, menthol cream (to reduce itching) and corticosteroids. There are, however, other types of treatment available that can help with managing the condition: 

  • Avoiding triggers that worsen the condition and cause a flare up.
  • Relaxation techniques, such as meditation or hypnosis, may help reduce symptoms and stress levels.
  • Managing diet has also been reported to impact urticaria symptoms - particularly eating plenty of foods like spinach, fish, tomato, yoghurt, chocolate, strawberry and meats. However, this is a hotly-debated topic and what works in one case may not help everyone suffering from hives.

If you’re experiencing what you think may be repeated attacks of hives, or aren’t sure - speak to a doctor today. Our GPs can diagnose the cause of the rash and if needed, provide advice and prescription medication to help tackle the condition.