Giant cell arteritis
Giant cell arteritis (GCA), is a condition that affects large and medium sized arteries in your body, in particular, the arteries in your neck and head.
On this page
- What causes giant cell arteritis?
- What are the signs and symptoms of giant cell arteritis?
- How is giant cell arteritis diagnosed?
- What is the treatment for giant cell arteritis?
- What if I already have sight loss due to giant cell arteritis?
- Are there any other conditions associated with giant cell arteritis?
GCA is sometimes referred to as temporal arteritis, as one of the more commonly affected arteries is the temporal artery at the side of your forehead (temple).
In GCA, the inner artery walls become inflamed or thickened (arteritis) with large inflammatory cells (giant cells). The inflammation causes the affected arteries to become swollen, greatly restricting the blood flow through them. If the blood flow becomes too restricted, the structures supplied by these arteries will be affected. If the artery which supplies the eye is affected, then this can cause sight loss in that eye. For this reason, GCA is considered an emergency.
This page contains a summary of our information on giant cell arteritis. To read our full information, download our factsheet:
What causes giant cell arteritis?
The cause of GCA is unknown. It’s not a common condition, and it rarely affects people under the age of 50 years old. It can affect people from 60 years of age, with the highest incidence seen in those over 70 years old. Women are more commonly affected by GCA than men.
What are the signs and symptoms of giant cell arteritis?
One of the first signs of GCA is a new onset frequent or constant headache, that can be severe in some case, which may come on suddenly or gradually. It is often at the side of your forehead, at your temples, and it may affect one or both sides of your head. The headache associated with GCA will probably not feel like any headache you’ve had before.
Scalp and temple tenderness
You may also feel that your temples and scalp are tender to touch, so that combing or brushing your hair feels uncomfortable. This is because the temporal artery is located close to the skin just in front of your ears and continues up to your scalp.
Pain around the eyes
Some people with GCA also experience pain around their eyes within the eye sockets.
Pain on chewing
Another early sign of GCA is pain and tiredness on chewing. This can be a cramp-like pain in your jaw which can make you stop eating. When you stop chewing the pain gets better. You may hear this referred to as jaw claudication and it is due to ischaemia in the muscles that help you to chew. Ischaemia can also cause pain in your tongue, mouth or ear.
If you have any of the symptoms outlined above, you should contact your GP urgently.
You may experience a temporary complete loss of vision in one eye which returns after a while. This is called amaurosis fugax and it is another sign of ischaemia. You may also experience double vision that you haven’t had before because the muscles controlling your eye movements may be affected.
Loss of vision
About 30-50 per cent of people who have untreated GCA will develop a permanent and severe loss of vision in one eye. Without immediate treatment, about a third of these people will develop sight loss in the other eye, often within a week of the first eye.
Therefore, it is vital that you see an ophthalmologist (hospital eye doctor) immediately in A&E if you experience sudden sight loss in one eye. Sudden loss of vision should always be investigated immediately by an ophthalmologist, even if your sight returns after a while, and even if you are not experiencing any of the other symptoms of GCA.
Some people lose their sight without having previously noticed any other symptom of GCA. If you experience sudden sight loss, you should go to A&E or to a hospital eye casualty department straight away to be seen urgently so that if treatment is needed, it can be given as soon as possible.
Other general health issues
Giant cell arteritis can be difficult to diagnose because its early symptoms resemble those of other common conditions.
Some people with GCA also experience more general symptoms such as weight loss, tiredness, flu-like symptoms, night sweats, fever and depression.
Usually, people have some symptoms of GCA before their sight is affected, so it’s very important to see your GP straight away if you are concerned that you might have a problem.
How is giant cell arteritis diagnosed?
If it is suspected that you have GCA, you will be given treatment straight away, even before all the results of the diagnostic tests are obtained. This is because it’s important to try to reduce any possible inflammation as quickly as possible, and to prevent blood flow in other arteries becoming restricted.
There are several things that your ophthalmologist or GP will check:
- The artery in your temple (the superficial temporal artery) may look and feel raised so that it cannot be flattened down on your head, and you may not be able to feel a pulse there when you touch it.
- Blood tests which check for signs of inflammation in your blood. These blood tests are non-specific tests, meaning they don’t pinpoint exactly where inflammation is in your body. Also, in some people the results are inconclusive. Therefore, other tests such as a temporal artery biopsy or an ultrasound scan are used to confirm the diagnosis.
What is the treatment for giant cell arteritis?
If it is suspected that you have GCA, emergency treatment will be started immediately with a high dose of steroids.
Steroids are medication that reduce inflammation in the body and, if GCA is suspected, you will be given steroid tablets to take even if your test results have not come through yet. The aim of this emergency treatment is to prevent sight loss and other rare complications such as stroke.
You will probably have to take steroid tablets for between 18 months and two years or even longer, with the dose being reduced gradually (tapered) over time, as the inflammation subsides. A small number of people may need to take steroids for the rest of their life.
Biological therapy treatments involve the use of drugs that alter a biological process occurring in your body.
With GCA, a number of proteins are produced by the body. One particular protein has been found to be very high in people who have GCA. Biological therapy treatment blocks the action of this protein so that the inflammation is reduced. This treatment is usually prescribed in addition to steroids that are being tapered (reduced over time).
It is given as a weekly injection under the skin (subcutaneous), in the thigh or upper arm. The drug is injected under the skin using a pre-filled syringe or a pen device and you may need to have these injections for up to a year, but your specialist will advise you about this. Steroids can lead to several unwanted side effects when taken at a high dose for a long time. By adding biological therapy to your treatment, lower doses of steroids can be given while still controlling your GCA.
What if I already have sight loss due to giant cell arteritis?
If it is suspected that your sight loss is due to GCA, you may be admitted to hospital for treatment or given treatment to use at home straight away.
If you are admitted, you may be given a high dose of steroids directly into your bloodstream via a drip (intravenous) over the next few days. If you are not admitted, you’ll be given high dose steroid tablets to use at home and then followed up by the hospital. The high dose steroids are given to try and bring down the swelling in your arteries as quickly as possible. Unfortunately, there is no treatment available that can bring back the sight loss caused by GCA so it is unlikely that the vision you have lost will return. The aim of this treatment is to prevent further sight loss in your other eye.
Are there any other conditions associated with giant cell arteritis?
About half the people with GCA have another condition called polymyalgia rheumatica (PMR) where the blood vessels supplying some of the larger muscles in your body are inflamed. The muscles particularly affected by PMR are those in your shoulders, neck, hips and back. These muscles can be painful and stiff, particularly on waking. It is possible to have GCA without having PMR as well. It is thought they might be different conditions with the same underlying cause, and they are both treated with steroids.
If you have been diagnosed with GCA with or without sight loss, it’s normal to find yourself worrying about the future and how you will manage if your vision changes. All these feelings are natural. We’re here to support you every step of the way, and to answer any questions you may have – just get in touch with our Sight Loss Advice Service.
Help to see things better
If both eyes are affected by GCA or the affected eye was your good eye and you have another sight problem in your other eye, you may need to make changes or use aids to make the most of your remaining sight. This may mean making things bigger, using brighter lighting or using colour to make things easier to see. You should ask your ophthalmologist, optometrist or GP about low vision aids and getting a low vision assessment. During this assessment with a low vision specialist, you’ll be able to discuss the use of magnifiers and aids to help you to see things more clearly.
You can also find out tips for making the most of your sight by downloading our booklet:
Page last reviewed: Sept. 1, 2022
Next review due: Jan. 31, 2023