Temporal arteritis is a subacute or acute inflammation of the arteries occurring usually in people aged 55 or older. Inflammatory and degenerative changes in the vessel wall are histologically characteristic, but the cause is not known. Although the name does not imply it, arteritis is active in other vessels such as the aorta, ophthalmic, and internal carotid. Prior to induration and swelling of the temporal artery, there may be generalized manifestations such as chills, fever, sweats, weakness, anorexia, weight loss, and nonlocalized pain. The end-result of arteritis may be occlusion or rupture of the vessel, with secondary tissue changes due to lack of blood supply. Frequently, partial or total loss of vision which can be temporary or permanent results from ophthalmic arteritis. In the past, temporal arteritis has often gone unrecognized. It is worthy of diagnostic effort now because effective treatment is available. Corticosteroid therapy gives symptomatic relief and arrests progress of the disease.