Giant cell arteritis (GCA)

What is giant cell arteritis?

Giant cell arteritis, or GCA, is one of a group of conditions referred to as vasculitis, meaning inflammation in the blood vessels.

It’s called an arteritis because it affects the arteries rather than the veins. It commonly affects the arteries of the skull, causing pain and tenderness over the temples. Because of this, GCA is often known as temporal arteritis.

Who gets giant cell arteritis?

  • Giant cell arteritis (GCA) is very rare in people younger than 50.
  • It’s more common in women than men.
  • It’s more common in people of northern European descent than in people of other races.
  • In the UK, 22 people in every 100,000 are affected.

GCA is quite often associated with a condition called polymyalgia rheumatica (PMR), which causes severe stiffness of the muscles, particularly in the shoulders and hips. About 15% of PMR patients also develop GCA, while 40–50% of people with GCA also have symptoms of PMR.


People with giant cell arteritis (GCA) may have a number of different symptoms. Most people will experience some, but not all, of these symptoms.

The most common symptoms of GCA are:

  • headache, with severe pain and tenderness over the temples and the scalp. It may be painful to brush your hair or shave
  • thickening or tenderness of the blood vessels at your temples
  • pain in the jaw or tongue when chewing (claudication)
  • fatigue
  • flu-like symptoms, night sweats or fever
  • weight loss
  • rarely, loss of vision. This can occur suddenly and may be only partial, but can sometimes be total. It’s usually temporary in the early stages, but without treatment loss of vision can become permanent
  • double vision.

You should see your doctor urgently (contact the out-of-hours service, if necessary) if you have visual disturbance or pain in the jaw or tongue. These symptoms suggest that you may be at greater risk of sight loss unless you receive prompt treatment.

Less commonly, GCA can affect other large blood vessels that could lead to pain when using the arm muscles or in the calves when walking. Occasionally, GCA can cause strokes or mini-strokes (also known as transient ischaemic attacks or TIAs).

People with GCA often have symptoms of polymyalgia rheumatica (PMR), with pain, stiffness and tenderness in the muscles of their shoulders, arms, hips and legs, especially in the mornings.


We don’t yet know the exact cause of GCA. However, we do know that it’s an autoimmune condition.

The immune system normally helps keep us healthy by fighting infection. However, in GCA, these defence mechanisms attack the healthy artery, causing inflammation. We don’t yet know why this happens. GCA isn’t directly inherited, but we know that genetic factors play some part.


A diagnosis of giant cell arteritis (GCA) is based on:

  • your symptoms
  • a clinical examination
  • blood tests
  • a temporal artery biopsy
  • an ultrasound scan.

It’s very important that your GP starts treatment straight away if GCA is suspected. However, you should also be referred promptly to a specialist to confirm the diagnosis. This may either be an ophthalmologist (an eye specialist) or a rheumatologist (a doctor who specialises in immune problems and problems with the joints and muscles).

What tests will I have for GCA?

Blood tests

These are used to check for signs of inflammation in the blood vessels. They’re useful in diagnosing GCA, but will also be repeated over time to check that the inflammation is controlled.

The key blood tests are the C-reactive protein (CRP) and the erythrocyte sedimentation rate (ESR). The levels measured by both these tests increase when there’s inflammation in the body. Your doctor may do one or the other of these blood tests. In most cases, ESP and CRP are high in people who have GCA. However, a normal result doesn't necessarily rule out GCA, and inflammation may have other causes such as infection.

Other blood tests may be done to look for other possible causes for your symptoms, including tests to check for inflammation in other blood vessels.


You may be asked to have a chest x-ray to rule out other conditions.

Your doctor may ask for an ultrasound scan of the arteries overlying the temple and in the armpit. This can be helpful in confirming a suspected GCA diagnosis, in combination with a biopsy. However, this type of scan isn't yet available in all hospitals.

Temporal artery biopsy

You may be given a biopsy even if you’ve already started on steroid treatment. The test should be done within 1-2 weeks of starting steroids. After this time, the steroids may be starting to work, making the test less reliable.

There are three main reasons for having the test:

  • It can confirm the diagnosis or sometimes suggest a different diagnosis. This is important to avoid unnecessary steroid treatment.
  • If your condition doesn’t improve with steroid treatments, it may be that you don’t have GCA. If the test shows no signs of GCA and your doctor is satisfied that you don’t have GCA the steroid treatment can be stopped.
  • It may help in assessing how severe the condition is and whether more powerful treatments are needed.

Using local anaesthetic, a small sample of artery from the scalp over your temple is removed and examined under a microscope. Your doctor will explain the procedure, including the risks and benefits, and you’ll be asked to sign a form consenting to the biopsy.

After the biopsy is taken you’ll have a wound about 3-4 cm (1-1½ in.) in length, close to the hairline. The wound will be covered with a dressing until your follow-up appointment about a week later, but you will be able to wash your hair with care. When the anaesthetic wears off you may need painkillers such as paracetamol for a time.

As with any surgical procedure you should look out for signs of infection, such as redness which starts to spread or a continuous discharge. Very rarely, the procedure may lead to temporary or permanent damage to the nerves which may result in numbness or a drooping brow. In patients who have narrowing of the arteries in the neck (carotid artery disease) there may be a very small risk of a stroke. If you have any concerns about the risks you should discuss them with your doctor beforehand.

Usually, the biopsy will contain enough sample to confirm the diagnosis. But sometimes it may not show evidence of GCA. If this happens, your doctor will decide whether to continue treatment based on blood tests and your overall condition.


Steroid tablets

Steroid tablets (usually prednisolone) are the most commonly used treatment for GCA. They're very effective and usually start to work within a few days. They work by reducing the activity of your immune system to reduce inflammation in the blood vessels. Your doctor will want to start treatment as soon as possible because of the possible risk of sight loss if you're not treated promptly.

You’ll usually be given a high dose of between 40 mg and 60 mg of prednisolone tablets every day for 3-4 weeks to begin with. If you’re well after that, and your blood tests have improved, your doctor will start reducing the dose. The specialist will want to see you regularly to monitor your progress.

It can be dangerous to suddenly stop taking your steroid tablets or to alter the dose unless your doctor tells you to. Normally your body produces its own steroids but this stops when you're on steroid treatment. When you come off steroid treatment it can take a little while for your body to start producing its own supply again.

It isn’t always possible to stop steroids completely, but you'll usually need to take them for 1-3 years because inflammation can come back (relapse) if your dose is reduced or stopped too quickly. Relapse is most common within the first 18 months of treatment. If you have a relapse, your steroid dose may have to be increased. Regular blood tests will show if there are signs of relapse.

If an increased dose of steroids doesn't stop relapses, your doctor may suggest you take an additional medication, such as methotrexate.

If you do develop visual symptoms, you may need to go to hospital urgently to be given steroids (methylprednisolone) through a drip into a vein.

There are some possible side-effects from steroids. Although these can be worrying, steroids are necessary to treat GCA. It’s important to start steroid treatment straight away to reduce the risk of sight loss.

You should be given a steroid card showing the dose of steroids you're on. If you need to see another doctor or healthcare professional (e.g. a dentist) you should tell them your steroid dose or show them the card. Depending on what the problem is you may need to increase your steroid dose temporarily or take them by a different method.

Other treatments

Steroids are the best first-line treatment available to get GCA under control quickly. However, if you have a relapse your doctor may suggest an additional medication to help reduce the dose of steroids. For example, a disease-modifying anti-rheumatic drug (DMARD) such as methotrexate, leflunomide or azathioprine.

Your doctor may suggest low-strength aspirin (75 mg) as it helps to protect against loss of vision.

As steroids have possible side-effects, your doctor may also suggest additional medications to protect you from these. You will be started on calcium and vitamin D supplements to protect your bones. Your doctor may also advise you to start another medication called a bisphosphonate to reduce the risk of developing osteoporosis.

Because steroids can affect the stomach lining, you may also be given a stomach-protecting tablet (for example, a proton pump inhibitor, or PPI) such as omeprazole. Bisphosphonates and PPIs will usually be started at the same time as the steroids.

Managing your symptoms


There are no particular foods that you should avoid if you have giant cell arteritis (GCA), but you should make sure you eat a healthy diet, containing plenty of calcium and vitamin D.

The richest sources of calcium are:

  • dairy products (milk, cheese, yogurt)
  • calcium-enriched soya milk
  • fish that are eaten with the bones (e.g. sardines).

Leafy green vegetables, beans, chick peas and some nuts and dried fruits also contain calcium. We recommend a daily intake of calcium of 1,000 milligrams (mg) or 1,500 mg if you’re over 60.

Vitamin D is needed for the body to absorb calcium, and is normally produced by the body when the skin is exposed to sunlight. However, it can also be obtained from food, especially from oily fish or supplements. Vitamin D is often added to soya milks and vegetable-based margarines. For many people, the most convenient way of getting enough vitamin D is to take supplements.

Rest and exercise

You should keep as fit and active as you can. This helps prevent osteoporosis, and may help to avoid weight gain and muscle weakness caused by steroid tablets.

Fatigue can be a major problem for some people even when on treatment. This can be a difficult symptom to manage, but some people find that gradual, well-paced exercise can help. Pacing and planning activities and setting realistic, achievable goals can improve your energy levels and well-being. If fatigue becomes a significant problem for you, an assessment with a specialist nurse or occupational therapist might help.

Help and support

People with GCA usually look well, even when the condition is severe (some of this may be due to the treatment with steroids). Because of this, friends and family may not understand why you feel unwell or find some things difficult. Some people also find it hard to come to terms with managing a long-term condition.

If GCA has caused partial or total loss of sight, this impairment should be registered to make sure you’re offered the benefits and support you’re entitled to.

Support and advice is available from a number of different organisations. There are also local self-help and patient support groups around the country.