Constant noise in the head— such as ringing in the ears—rarely indicates a serious health problem, but it sure can be annoying. Here’s how to minimize it.
Tinnitus (pronounced tih-NITE-us or TIN-ih-tus) is sound in the head with no external source. For many, it’s a ringing sound, while for others, it’s whistling, buzzing, chirping, hissing, humming, roaring, or even shrieking. The sound may seem to come from one ear or both, from inside the head, or from a distance. It may be constant or intermittent, steady or pulsating.
Almost everyone has had tinnitus for a short time after being exposed to extremely loud noise. For example, attending a loud concert can trigger short-lived tinnitus. Some medications (especially aspirin and other nonsteroidal anti-inflammatory drugs taken in high doses) can cause tinnitus that goes away when the drug is discontinued. When it lasts more than six months, it’s known as chronic tinnitus. As many as 50 to 60 million people in the United States suffer from this condition; it’s especially common in people over age 55 and strongly associated with hearing loss. Many people worry that tinnitus is a sign that they are going deaf or have another serious medical problem, but it rarely is.
Most tinnitus is subjective, meaning that only you can hear the noise. But sometimes it’s objective, meaning that someone else can hear it, too. For example, if you have a heart murmur, you may hear a whooshing sound with every heartbeat; your clinician can also hear that sound through a stethoscope. Some people hear their heartbeat inside the ear — a phenomenon called pulsatile tinnitus. It’s more likely to happen in older people, because blood flow tends to be more turbulent in arteries whose walls have stiffened with age. Pulsatile tinnitus may be more noticeable at night, when you’re lying in bed and there are fewer external sounds to mask the tinnitus. If you notice any new pulsatile tinnitus, you should consult a clinician, because in rare cases it is a sign of a tumor or blood vessel damage.
The course of chronic tinnitus is unpredictable. Sometimes the symptoms remain the same, and sometimes they get worse. In about 10% of cases, the condition interferes with everyday life so much that professional help is needed.
While there’s no cure for chronic tinnitus, it often becomes less noticeable and more manageable over time. You can help ease the symptoms by educating yourself about the condition — for example, understanding that it’s not dangerous. There are also several ways to help tune out the noise and minimize its impact.
|Auditory pathways and tinnitus Sound waves travel through the ear canal to the middle and inner ear, where hair cells in part of the cochlea help transform sound waves into electrical signals that then travel to the brain’s auditory cortex via the auditory nerve. When hair cells are damaged — by loud noise or ototoxic drugs, for example — the circuits in the brain don’t receive the signals they’re expecting. This stimulates abnormal activity in the neurons, which results in the illusion of sound, or tinnitus.|
What’s going on?
Most people who seek medical help for tinnitus experience it as subjective, constant sound like constant ringing in the ears or a buzzing sound in the ear, and most have some degree of hearing loss. Things that cause hearing loss (and tinnitus) include loud noise, medications that damage the nerves in the ear (ototoxic drugs), impacted earwax, middle ear problems (such as infections and vascular tumors), and aging. Tinnitus can also be a symptom of Meniere’s disease, a disorder of the balance mechanism in the inner ear.
Tinnitus can arise anywhere along the auditory pathway, from the outer ear through the middle and inner ear to the brain’s auditory cortex, where it’s thought to be encoded (in a sense, imprinted). One of the most common causes of tinnitus is damage to the hair cells in the cochlea (see “Auditory pathways and tinnitus”). These cells help transform sound waves into nerve signals. If the auditory pathways or circuits in the brain don’t receive the signals they’re expecting from the cochlea, the brain in effect “turns up the gain” on those pathways in an effort to detect the signal — in much the same way that you turn up the volume on a car radio when you’re trying to find a station’s signal. The resulting electrical noise takes the form of tinnitus — a sound that is high-pitched if hearing loss is in the high-frequency range and low-pitched if it’s in the low-frequency range. This kind of tinnitus resembles phantom limb pain in an amputee — the brain is producing abnormal nerve signals to compensate for missing input.
Most tinnitus is “sensorineural,” meaning that it’s due to hearing loss at the cochlea or cochlear nerve level. But tinnitus may originate in other places. Our bodies normally produce sounds (called somatic sounds) that we usually don’t notice because we are listening to external sounds. Anything that blocks normal hearing can bring somatic sounds to our attention. For example, you may get head noise when earwax blocks the outer ear.
|Some drugs that can cause or worsen tinnitus Aspirin and other nonsteroidal anti-inflammatory drugs, including ibuprofen (Motrin) and naproxen (Aleve, Naprosyn) Certain antibiotics, including ciprofloxacin (Cipro), doxycycline (Vibramycin, others), gentamicin (Garamycin), erythromycin (Ery-Tab, others), tetracycline (Sumycin), tobramycin (Nebcin), and vancomycin (Vancocin) Antimalarial drugs such as chloroquine and quinine Certain anticonvulsants, including carbamazepine (Tegretol, others) and valproic acid (Depakote, others)|