Giant cell arteritis (GCA) is treatable, and complications can be avoided when treatment is started early enough. As blindness and other severe consequences can come on suddenly, doctors will start treatment as soon as the disease is suspected; confirmation of diagnosis can be done after starting treatment.
The medication usually used is prednisone*, a corticosteroid that reduces inflammation. Treatment begins with a high dose to bring down the inflammation in the arteries under control. This is then slowly tapered to a lower dose that is called the "maintenance dose," as recommended by the doctor. A person who has vision problems will often be given methylprednisolone intravenously to start. Long-term use of corticosteroids poses a risk of serious side effects, and maintaining the lowest dose possible helps reduce those risks.
Some people need to keep taking low doses for a year or two before their doctor can be sure that symptoms won't return. Others may need to take prednisone for 5 to 10 years or indefinitely. Sometimes, symptoms recur a few times early in treatment and the dosage has to be temporarily raised. GCA usually does not recur after treatment is finally stopped, but a person with aortic disease needs to be monitored regularly by their doctor once it occurs.
The following side effects are associated with corticosteroid use, but they are much less likely with the lower doses given for GCA after gradually tapering from the initial high dose to a lower dose:
- degeneration of hip or shoulder bones
- diabetes
- easy bruising
- fluid retention and weight gain
- glaucoma
- higher blood pressure
- increased susceptibility to infections, including serious infections
- osteoporosis (your doctor may recommend taking calcium and vitamin D supplements to help prevent osteoporosis)
- reactivation of hidden tuberculosis or other chronic infections - people who test positive for tuberculosis need to take tuberculosis-preventive medication
- rounding of the facial features
- slower healing of wounds
- stomach irritation
- muscle weakness (sometimes permanent)
Prednisone is also used to treat polymyalgia rheumatica, but at a much lower dose. Symptoms are usually eliminated within a day or two or up to one week after the first dose. The dose is then slowly reduced and maintained at lower doses for at least several years and sometimes longer.
The medication tocilizumab may be given with oral steroids, or by itself after a steroid regimen has been completed. Other immunosuppressant medications, such as azathioprine, methotrexate, or biologics have not been clearly shown to be helpful, though some experts feel they may have some value.
Doctors may also prescribe low-dose (81 mg daily) acetylsalicylic acid (ASA) to help lower the risk of blindness or stroke. These complications may result if the blood flow carrying oxygen to the optic nerve or to the brain is cut off due to the arteritis.
There's no easy way to prevent arteritis, but a healthy lifestyle and not smoking are always important.
Above all, see a doctor if you have the symptoms listed in the "Symptoms and Complications" section. As many as 1 in 5 people with this disease will go blind without treatment, but prompt treatment can make a big difference. Not all physicians recognize the early clues. Rheumatology is the field with most expert experience in GCA and PMR. You should also get your eyesight checked every 2 years if you're over 50 years of age, and every year if you have diabetes.