A condition in which there the perception of sound in one or both ears or in the head when no external sound is present. It is often referred to as "ringing in the ears", although some people hear hissing, roaring, whistling, chirping, or clicking. Tinnitus can be intermittent or constant, with single or multiple tones, and its perceived volume can range from subtle to shattering. Causes may include noise-induced hearing loss, wax build-up in the ear canal, ear or sinus infections, jaw misalignment, cardiovascular disease, head or neck trauma, certain types of tumours, a side effect of some medications or as a symptom of disorders such as hypothyroidism, hyperthyroidism, lyme disease and fibromyalgia.
The above terms and definitions are part of the Taxonomy of Human Services, used here by permission of INFO LINE of Los Angeles.