Get help now
- Go to A&E or call 999 if you have any sudden change in your vision, such as blurring, double vision, a curtain over part of your sight or loss of vision in one eye, alongside a headache, scalp tenderness or jaw pain.
- Contact your GP for a same-day appointment, or call NHS 111, if you are over 50 and have a new headache that feels different from usual, tenderness over your temples or scalp, or pain in your jaw when you chew.
- If you already have polymyalgia rheumatica (PMR), tell whoever you speak to that you have PMR.
- Do not wait to see if it settles by itself. Early treatment protects your sight.
Quick answer: Giant cell arteritis (GCA) is inflammation of medium and large arteries, especially those in the head. It mainly affects people over 50 and can cause permanent sight loss if it is not treated quickly. A new headache, a tender scalp, jaw pain when chewing or any change in vision needs same-day medical help. Treatment with steroids usually starts straight away.
What is giant cell arteritis?
Giant cell arteritis, sometimes called temporal arteritis, is a type of vasculitis. That means the immune system causes inflammation in the walls of blood vessels. In GCA the arteries most often affected run up the sides of the head, by the temples, and supply the scalp, jaw and eyes. When they become inflamed they can narrow, which reduces blood flow. If the arteries that supply the eye are affected, sight can be damaged, sometimes suddenly and permanently.
GCA almost never occurs before the age of 50 and becomes more common with each decade after that. It is more common in women than in men. It is closely linked with polymyalgia rheumatica, a condition that causes pain and stiffness in the shoulders and hips. Some people have both at the same time, and some people with PMR go on to develop GCA later.
Symptoms to look out for
Symptoms can come on over a few days or weeks. Not everyone has all of them, and they can be easy to put down to something else. The ones that matter most are:
- A new headache, often around the temples, that is different from any headache you have had before. It may be on one side or both.
- Scalp tenderness, for example it hurts to brush or comb your hair or rest your head on a pillow.
- Jaw pain when chewing that eases when you stop. Doctors call this jaw claudication, and it is an important clue.
- Changes in vision, such as blurring, double vision, flashing lights or a shadow over part of your vision, even if they come and go.
- Feeling generally unwell, with tiredness, a low-grade temperature, night sweats, poor appetite or weight loss.
- Shoulder and hip stiffness in the mornings, if you also have PMR.
Less commonly, GCA can cause pain in the tongue, a sore throat, arm pain when using your arms, or a tender, thickened artery at the temple that you can feel.
Why speed matters
The biggest risk with GCA is sight loss. Once sight has been lost because of GCA, it usually does not come back. That is why the NHS treats suspected GCA as urgent and why doctors often start treatment before all the test results are back. It is always better to be checked and reassured than to wait.
If you are worried, say the words "I am worried this could be giant cell arteritis" when you call your GP practice or NHS 111. That helps the person triaging your call understand the urgency.
How GCA is diagnosed
Your GP or an emergency doctor will ask about your symptoms, examine your head and scalp, and check your eyes and blood pressure. You are likely to have:
- Blood tests to look for inflammation, usually CRP and ESR. Raised levels support the diagnosis but are not proof on their own. Read more in our guide to getting to blood tests if travel is difficult.
- An urgent referral to a specialist service. Many hospitals run a fast-track GCA pathway so you can be seen within days, often by a rheumatologist.
- An ultrasound scan of the arteries in the temples and sometimes the armpits, which can show inflammation in the artery walls.
- A temporal artery biopsy in some hospitals, where a tiny piece of artery is removed under local anaesthetic and looked at under a microscope.
- An eye examination by an eye specialist if you have any visual symptoms.
Other scans, such as a PET-CT, are sometimes used if the doctors think larger arteries, such as the aorta, may be involved.
Treatment
The main treatment for GCA is a steroid medicine, usually prednisolone, started at a high dose to switch off the inflammation quickly. If you have visual symptoms, you may be given steroids through a drip in hospital at first. Most people notice their headache and general symptoms improve within a few days.
Once the inflammation is under control, the steroid dose is reduced slowly over many months. Your team will set the pace based on your symptoms and blood tests. Treatment often lasts one to two years, and sometimes longer. Never stop steroids suddenly or change the dose yourself, because your body needs time to adjust and stopping abruptly can make you seriously unwell. Always follow your own rheumatology team's plan.
Because long courses of steroids can affect bones, blood sugar, blood pressure, mood and sleep, your team may also offer:
- Bone protection, such as calcium and vitamin D and sometimes a bisphosphonate. Our guide to bone protection on steroids explains why.
- Stomach protection, if you are at risk of indigestion or ulcers.
- Regular checks of blood sugar, blood pressure and weight.
- A steroid emergency card, which you should carry at all times. See our guide to the steroid emergency card.
Some people need an extra medicine to help control GCA and allow the steroid dose to come down. Options include methotrexate or a biologic called tocilizumab, which NICE has approved for some people with GCA that keeps coming back or does not settle. Your specialist will explain whether these are suitable for you.
Living with GCA
Most people with GCA respond well to treatment, and many eventually come off steroids completely. The months of treatment can still be hard. Steroid side effects, worry about sight and fatigue are all common. These steps can help:
- Learn the signs of a flare, such as your headache or jaw pain returning, and agree with your team how to contact them quickly.
- Keep a simple diary of symptoms and your steroid dose, so appointments are easier.
- Stay as active as you can. Gentle walking and strength exercises help protect bones and muscles while on steroids. See our steroids guide for more.
- Ask about vaccinations, such as flu, COVID-19 and pneumonia, because steroids can make infections more likely.
- Have regular eye tests with an optometrist, and tell them you have had GCA.
GCA and polymyalgia rheumatica
If you live with PMR, it is worth knowing the GCA warning signs well, because the two conditions overlap. A new headache, scalp soreness, jaw pain on chewing or any visual disturbance while you have PMR needs same-day advice, even if your PMR is well controlled. Your PMR steroid dose is usually lower than the dose used for GCA, so it may not be enough to prevent GCA. Our guides to PMR symptoms and PMR steroid tapers have more detail.
Frequently asked questions
Is giant cell arteritis an emergency?
It is treated as urgent because it can cause permanent sight loss. Any change in vision needs A&E or 999. A new headache, scalp tenderness or jaw pain on chewing if you are over 50 needs a same-day GP appointment or a call to NHS 111.
Can you get GCA under the age of 50?
It is very rare under 50. Headaches in younger people usually have other causes, but any severe, sudden or unusual headache should still be checked.
How long will I be on steroids for GCA?
Most people take steroids for one to two years, reducing the dose slowly over time. Some need them for longer. Your rheumatology team will guide the pace, and you should never stop or change the dose yourself.
Can GCA come back?
Yes, flares can happen, particularly as the steroid dose is reduced. Tell your team promptly if your symptoms return. Extra medicines can help if flares keep happening.
Will my sight come back if GCA affected it?
Sight lost because of GCA usually does not return, which is why fast treatment matters. Treatment aims to protect the other eye and any remaining sight.
Is GCA the same as a migraine?
No. Migraine usually starts earlier in life and follows a familiar pattern. GCA causes a new type of headache in people over 50, often with scalp tenderness, jaw pain or visual symptoms.
Sources and further reading
- NHS: Giant cell arteritis
- NICE CKS: Giant cell arteritis
- NICE TA518: Tocilizumab for treating giant cell arteritis
- NHS: Polymyalgia rheumatica
This guide is for general education and is not a substitute for personal medical advice. Everyone's situation is different, so always follow the advice of your own GP, pharmacist or rheumatology team. If you feel very unwell, call 999 or go to A&E. For urgent advice, contact NHS 111.