Giant cell arteritis (GCA) is inflammation in the lining of your arteries, most often in the arteries of your head. It’s a pretty rare disease.

Since many of its symptoms are similar to those of other conditions, it can take some time to diagnose.

Around half of people with GCA also have symptoms of pain and stiffness in the shoulders, hips, or both, known as polymyalgia rheumatica.

Learning that you have GCA is a big step. Your next question is how to treat it.

It’s important to get started on treatment as soon as you can. Not only are symptoms like headaches and face pain uncomfortable, but the disease can lead to blindness without prompt treatment.

The right treatment can manage your symptoms, and it might even cure the condition.

Treatment usually involves high doses of a corticosteroid drug like prednisone. Your symptoms should start to improve very quickly on the medication — within 1 to 3 days.

The downsides of prednisone are its side effects, some of which can be serious. Most people using prednisone experience at least one of these side effects:

  • weak bones that can fracture easily
  • weight gain
  • infections
  • high blood pressure
  • cataracts or glaucoma
  • high blood sugar
  • muscle weakness
  • problems sleeping
  • easy bruising
  • water retention and swelling
  • stomach irritation
  • blurred vision

Your doctor will check you for side effects and treat any you do have. For example, you can take medications like bisphosphonates or calcium and vitamin D supplements to strengthen your bones and prevent fractures.

Most side effects are temporary. They should improve as you taper off prednisone.

Yes. This medication is very effective at preventing vision loss, the most serious complication of GCA. That’s why it’s important to start taking this medication as soon as you can.

If you lost vision before you started taking prednisone, it won’t come back. But your other eye may be able to compensate if you stay on track with this treatment.

After about a month of taking prednisone, your doctor will start to taper down your dose by about 5 to 10 milligrams (mg) a day.

For example, if you started at 60 mg per day, you may drop to 50 mg and then 40 mg. You’ll stay on the lowest dose possible needed to manage your inflammation.

How quickly you taper down your dose depends on how you feel and your test results of inflammatory activity, which your doctor will monitor throughout your treatment.

You may not be able to completely stop the medication for a while. Most people with GCA will need to take a low dose of prednisone for 1 to 2 years.

Tocilizumab (Actemra) is a newer medication the Food and Drug Administration approved in 2017 to treat GCA. You may receive this drug as you taper off prednisone.

It comes as an injection your doctor gives under your skin, or an injection you give yourself every 1 to 2 weeks. Your doctor might keep you on just Actemra once you stop taking prednisone.

Actemra is effective at keeping GCA in remission. It can also reduce the need for prednisone, which would cut down on the side effects. But because Actemra affects your immune system, it could increase your risk for infection.

It’s common for headaches and other symptoms to return once you start tapering off prednisone. Doctors don’t know exactly what causes these relapses. Infections are one possible trigger.

If your symptoms do come back, your doctor might bump up your prednisone dose to help manage them. Or they may prescribe an immune-suppressing drug like methotrexate (Trexall), or have you begin treatment with Actemra.

After a year or two of taking prednisone, your symptoms should disappear. GCA rarely comes back after it’s successfully treated.

Medication isn’t the only way to manage GCA. Taking good care of yourself can also help you feel better.

Eat a diet that minimizes inflammation in your body. Good choices are anti-inflammatory foods like fatty fish (salmon, tuna), nuts and seeds, fruits and vegetables, olive oil, beans, and whole grains.

Try to be active every day. Choose exercises that aren’t too hard on your joints, like swimming or walking. Alternate activities with rest so you don’t get overworked.

Living with this condition can be very stressful. Talking with a mental health professional or joining a GCA support group can help you cope better with this condition.

GCA can cause uncomfortable symptoms and possibly blindness if it’s not treated. High-dose steroids and other medications can help you manage these symptoms and prevent vision loss.

Once you’re on a treatment plan, it’s important for you to stick with it. See your doctor if you have any trouble taking your medication, or if you develop side effects you can’t tolerate.