context: Temporal arteritis is a disease that causes your arteries -- blood vessels that carry oxygen from your heart to the rest of your body -- to become inflamed. It usually happens to the large and medium-sized temporal arteries that run along both sides of your head. The cells of these inflamed arteries look huge under a microscope. That is why temporal arteritis is also called giant cell arteritis. The swelling slows blood flow through your arteries, and that can cause symptoms like headaches and pain in your face and joints. Left untreated, narrowed arteries can cause vision problems and blindness. Medication can help your symptoms and prevent serious health issues. It's an autoimmune disease. That means your immune system mistakenly attacks your body's healthy tissues. In temporal arteritis, immune cells react against blood vessels and make them inflamed. Doctors don't know what triggers this, but you're more likely to get it if you're: Over 50 Female Of European descent -- especially if your family is from a country in Scandinavia ( Norway, Sweden, Denmark, or Finland) One of the main symptoms of temporal arteritis is a headache you feel in your temples and scalp. The pain can be severe. Other symptoms may include: Fever Fatigue Pain in your jaw when you chew Pain in your face Vision problems such as blurred vision, double vision, or sudden vision loss Pain in your shoulders, arms, neck, and hip Appetite loss Weight loss Cough Sore throat Tongue pain If you notice these symptoms, let your doctor know. About half of people with temporal arteritis have polymyalgia rheumatica ( PMR) as well. PMR is an inflammatory condition that also causes swelling, but in your joints. Symptoms include stiffness and aching in your arms, neck, lower back, and thighs. It can be treated with medication and usually goes away within a few years. It's not clear how or why the two conditions are related. Your doctor will do an exam and ask about your symptoms. They'll also look for swelling and a weak pulse in the temporal artery in your scalp. You may need a biopsy of the temporal artery. If so, your doctor will numb an area of your scalp and remove a small piece of the temporal artery. A doctor will then check it under a microscope. The cells of an inflamed artery look very large under the microscope. Your doctor also might do one or more of these: Blood test. A sample is taken to check for signs of inflammation in your body. CT scan (computerized tomography). Several X-rays taken from different angles are put together to show more information about your arteries. MRI scan (magnetic resonance imaging). Powerful magnets and radio waves are used to make detailed images of your arteries. When arteries are inflamed, blood can't move as easily through them. Temporal arteritis can keep oxygen from getting to your eyes, and this can damage them. You might need to see an eye doctor to check for this. If you have temporal arteritis, your doctor will start you on medication right away to prevent vision loss and other problems. The main treatment is high doses of steroids, such as prednisone, to reduce inflammation in the arteries. You'll take this medication by mouth every day. Most people stay on a steroid for 1 to 2 years. Your doctor will do blood tests every few months to see if the inflammation in your arteries has gone down. As it does, your doctor will lower the dose of your medicine. These medications can weaken your bones, so your doctor might suggest regular bone mineral density tests. Your doctor may suggest you take calcium and vitamin D supplements, along with a prescription drug called a bisphosphonate, to slow down or prevent bone damage. Other medications that may be used include methotrexate, a drug commonly used to treat cancer as well as rheumatoid arthritis and psoriasis, and a biologic drug called tocilizumab ( Actemra). Tocilizumab is given as an injection under the skin to lessen the amount of steroids a person needs. This medicine may be used along with steroids. You also might take aspirin to thin your blood and prevent clots.