While tinnitus is as varied as its causes, it can be grouped into two categories: tonal and non-tonal. Tonal tinnitus is more common and describes the perception of a near-continuous sound or overlapping sounds with a well-defined frequency (e.g., whistling, ringing, buzzing). Non-tonal forms of tinnitus include humming, clicking, crackling, and rumbling.
When a medication is ototoxic, it has a toxic effect on the ear or its nerve supply. In damaging the ear, these drugs can cause side effects like tinnitus, hearing loss, or a balance disorder. Depending on the medication and dosage, the effects of ototoxic medications can be temporary or permanent. More than 200 prescription and over-the-counter medicines are known to be ototoxic, including the following:
Vascular issues. Some people have blood vessels near their ears that are capable of causing tinnitus. I have found that if the blood pressure is elevated, this increased pressure can cause that dreaded ringing in your ears or even a whooshing sound. Because pregnant women often have elevated blood pressure, they are easily susceptible to tinnitus. Tinnitus caused by pregnancy should go away with an over the counter tinnitus treatment and once the baby is born. An overactive thyroid has also been shown to causes vascular issues that bring on tinnitus.
Cartoon of the middle ear showing muscles that attach to ossicles (ear bones), and ear drum. The stapedius is attached to the stapes (of course -- horseshoe object above), while the tensor tympani is attached to the ear drum. While useful, be aware that there are multiple errors in this illustration from Loyola Medical School. With permission, from: http://www.meddean.luc.edu/lumen/meded/grossanatomy/dissector/mml/images/stap.jpg
Tinnitus affects every layer of society, and there has been increasing support for awareness. Recently, musicians who are affected by tinnitus have come together to create awareness for the disorder. Artists including Chris Martin of Coldplay and Black Eyed Peas have created a compilation album to help raise funds towards finding a cure for tinnitus. In the United States, the Department of Defense has invested millions of dollars into investigations of tinnitus sound therapies. In addition, the American Tinnitus Association makes efforts to lobby the US government to provide support for tinnitus sufferers.
Millions of Americans experience tinnitus, often to a debilitating degree, making it one of the most common health conditions in the country. The U.S. Centers for Disease Control estimates that nearly 15% of the general public — over 50 million Americans — experience some form of tinnitus. Roughly 20 million people struggle with burdensome chronic tinnitus, while 2 million have extreme and debilitating cases.1