Temporal Arteritis (Giant Cell Arteritis)

Causes

• Age: GCA almost exclusively affects people over the age of 50, with the average age of onset around 70.
• Sex: Women are about two to three times more likely to develop GCA than men.
• Genetics: There appears to be a genetic predisposition, as GCA is more common in people of Northern European descent.
• Polymyalgia Rheumatica (PMR): A significant percentage of people with PMR either have or will develop GCA, and vice versa.
• Environmental factors: Some research suggests that infections or other environmental triggers might play a role in initiating the condition in genetically susceptible individuals, but no specific trigger has been definitively identified.

Symptoms

• Persistent, severe headache: Often localized to the temples, but can be on one or both sides of the head, or in the back of the head. The pain may be throbbing or sharp.
• Scalp tenderness: Pain or tenderness when touching the scalp, especially over the temporal arteries.
• Jaw pain (jaw claudication): Pain or cramping in the jaw muscles that worsens with chewing.
• Vision problems: Sudden, temporary, or permanent loss of vision in one or both eyes (often described as a "curtain coming down"), double vision, or blurred vision. This is a medical emergency.
• Fatigue: General tiredness and weakness.
• Fever: Low-grade fever is common.
• Weight loss: Unexplained weight loss.
• Loss of appetite.
• Muscle aches and stiffness: Similar to polymyalgia rheumatica, affecting the shoulders, neck, and hips.

Diagnosis

• Medical history and physical examination: The doctor will ask about your symptoms, especially headaches, jaw pain, and vision changes. They will also examine your temporal arteries, which may be tender, swollen, or have a reduced pulse.
• Blood tests:
  • Erythrocyte Sedimentation Rate (ESR): A significantly elevated ESR is a strong indicator of inflammation.
  • C-reactive protein (CRP): Another marker of inflammation that is typically high in GCA.
  • Other blood tests may be done to rule out other conditions.
• Temporal artery biopsy: This is often considered the gold standard for diagnosis. A small sample of the temporal artery is surgically removed and examined under a microscope for signs of inflammation (giant cells).
• Imaging tests:
  • Ultrasound: High-resolution ultrasound of the temporal arteries can show signs of inflammation (e.g., "halo sign").
  • MRI or CT angiography: May be used to visualize larger arteries and assess for inflammation or narrowing.
  • PET scan: Can sometimes identify inflammation in large arteries throughout the body.

Treatment

• High-dose corticosteroids:
  • Oral corticosteroids (e.g., prednisone) are the cornerstone of treatment and are started immediately, often even before a biopsy confirms the diagnosis, especially if vision changes are suspected.
  • The initial dose is high to rapidly control inflammation and protect vision.
  • The dose is gradually tapered over many months to years, as GCA is a chronic condition that requires long-term management.
• Immunosuppressants:
  • In some cases, other immunosuppressive medications (e.g., methotrexate, tocilizumab) may be added to allow for a lower corticosteroid dose, reduce side effects, or manage refractory disease.
• Aspirin: Low-dose aspirin may be recommended to help prevent blood clots and reduce the risk of stroke or heart attack.
• Bone-preserving medications: Calcium, Vitamin D, and bisphosphonates are often prescribed to counteract the bone-thinning side effects of long-term corticosteroid use.
• Monitoring: Regular follow-up with your doctor is essential to monitor symptoms, inflammation markers (ESR, CRP), and adjust medication dosage. Close monitoring for potential complications is also crucial.

Living With Giant Cell Arteritis Through the Long Taper

The emergency phase of giant cell arteritis lasts days; the treatment lasts a year or two, and most of its harm comes from the steroids rather than the disease. Knowing what a relapse feels like and how the steroid burden is reduced makes that stretch safer.

What to expect from prednisone

Headache, jaw pain, and scalp tenderness usually fade within days of starting prednisone, and that quick response supports the diagnosis. The dose then comes down over twelve to eighteen months or longer, and about half of people relapse along the way, most often at low doses. A returning headache, jaw ache with chewing, or the shoulder and hip stiffness of polymyalgia rheumatica matters more than a blood test, because the sedimentation rate and CRP can drift up with a cold. Never stop prednisone abruptly; after months of use a sudden stop causes adrenal insufficiency.

Reducing the steroid burden

Tocilizumab, a weekly injection, is approved for giant cell arteritis and roughly doubles the chance of staying in remission on a faster taper, so it is offered from the start to people with diabetes, osteoporosis, or a relapse. It suppresses the CRP completely, so symptoms become the only relapse signal, and it raises infection risk. Methotrexate is the older, weaker alternative.

Protecting bones, sugar, and eyes

A bone density scan and a bisphosphonate such as alendronate are arranged at the outset, along with calcium and vitamin D; our bone health after 50 article covers the details. Blood sugar and blood pressure are checked at each visit, a yearly eye exam watches for cataracts and glaucoma, and shingles, pneumonia, and flu vaccines are brought current before immune-suppressing drugs are added.

The large vessels, years later

Aortic inflammation is common and can leave an aneurysm a decade after the headaches are forgotten, so the aorta is imaged at diagnosis and periodically afterward; the abdominal aortic aneurysm page explains surveillance. Arm pain with use or a blood pressure that differs between arms points to narrowing of the arm arteries. Our polymyalgia and temporal arteritis article covers the overlap.

The signs that cannot wait

Any new visual symptom, a gray curtain, double vision, or a brief blackout of one eye, is a same-day emergency at any point in treatment, because the second eye often follows within days. Stroke symptoms and a new severe headache on a low dose are treated the same way. Our musculoskeletal team coordinates care with rheumatology. The American College of Rheumatology and NIAMS publish patient guidance.

If you are tapering prednisone for giant cell arteritis and a headache or jaw pain has returned, or nobody has discussed a steroid-sparing drug, schedule a visit.