Giant Cell Arteritis

Giant cell arteritis (GCA) is a type of vasculitis, a group of diseases whose main feature is inflammation of blood vessels. In GCA, the vessels most often involved are the arteries of the scalp and head, especially the arteries over the temples, which is why another term for GCA is “temporal arteritis.” GCA can overlap with polymyalgia rheumatica (PMR). At some point, 5 – 15% of patients with PMR will have a diagnosis of GCA. About 50 percent of patients with GCA have symptoms of PMR. The two conditions may occur at the same time or on their own. It also affects the same types of patients as does PMR. It occurs only in adults, usually over age 50, in women more than men, and in whites more than non-whites.

What Are the Signs/Symptoms?

The most common symptom of GCA is a new headache, usually around the temples, but headache can occur anywhere. Other symptoms include fatigue, loss of appetite, weight loss, or flu-like feeling. There may be pain in the jaw from chewing. If GCA spreads to the blood supply of the eye, eyesight can be affected. Permanent loss of vision in GCA can occur suddenly, but proper treatment can prevent this complication. It is vital that patients who have active or inactive PMR report any symptoms of new headache, changes in vision, or jaw pain to their doctors. There is no simple blood test to confirm the diagnosis of GCA. The erythrocyte sedimentation rate (or sed rate) is a blood test that measures inflammation but finding alone is not proof for GCA. In some cases, an ultrasound of the temporal arteries can be done. It is common to do biopsy of the temporal artery to confirm.

What Are Common Treatments?

GCA treatment should start immediately after diagnosis to prevent vision loss. First-line treatment usually is 40-60 mg per day of prednisone, a corticosteroid. Headaches and other symptoms often ease quickly with treatment, and the sed rate drops. After about a month of high-dose corticosteroids, the dose is tapered. For most patients, prednisone dose is reduced to 5-10 mg per day over a few months. Patients often taper off prednisone completely after one to two years. GCA can return after treatment. In May 2017, tocilizumab was approved for the treatment of GCA which is given intravenous or subcutaneous injection to help decrease the need for corticosteroid.

Living with GCA

Side effects are more common with higher doses of corticosteroids. For example, corticosteroid treatment can cause bone loss, so your doctor may want you to get a bone density test and suggest vitamin D, calcium, or bisphosphonates to prevent osteoporosis and bone fractures. Other steroid side effects include jittery moods, weight gain, poor sleep, muscle weakness, cataracts, and skin bruising. Most steroid side effects are temporary and can be managed.

Updated February 2023 by Howard Yang, MD, and reviewed by the American College of Rheumatology Committee on Communications and Marketing.

This information is provided for general education only. Individuals should consult a qualified health care provider for professional medical advice, diagnosis and treatment of a medical or health condition.