Multiple: Laryngitis

Definition

Laryngitis is defined as inflammation or irritation of the larynx, which is the voice box that lies at the base of the throat just above the windpipe. It is a condition or symptom rather than a distinctive disease. Acute laryngitis is defined as lasting three weeks or less; laryngitis that lasts longer than three weeks is called chronic laryngitis.

Description

Laryngitis occurs when the vocal folds (or vocal cords) swell as a result of infection or another cause of inflammation. The vocal folds are two bands of tissue that stretch across the larynx. Under normal circumstances, when a person wants to speak, the vocal folds tighten. Air from the lungs is forced through the smaller space between the bands of muscle, causing them to vibrate. Lengthening, shortening, tightening, and loosening of the cords allows a person to control the pitch of the voice. When the vocal folds swell up due to irritation or inflammation, they cannot vibrate easily, which causes the voice to sound hoarse, raspy, or faint.

Demographics

Laryngitis is so common in the general population that no exact statistics are kept. Most people treat acute laryngitis at home without visiting a doctor, particularly if the voice problem seems to be a side effect of a cold or the flu. According to one study, acute laryngitis is most common in adults between the ages of eighteen and forty. It appears to affect both sexes and all races equally. Chronic laryngitis is more common in adults over fifty and in people whose occupations expose them to irritating chemicals.

People who smoke, people with asthma, firefighters, and singers or public speakers are at greater risk of laryngitis than the general population.

Causes and Symptoms

The most common single cause of acute laryngitis is an upper respiratory infection caused by a virus, most often a cold or influenza virus. Other viruses, such as those that cause chickenpox, mumps, or measles, can also cause laryngitis.

Home Care for Laryngitis

Acute laryngitis caused by a cold or the flu can usually be treated at home:

• Keep the air in the house moist by using a humidifier.
• Moisten the tissues of the throat by breathing in the steam from a hot shower or holding the heat over a bowl of hot steaming water.
• Drink plenty of fluids.
• Use throat lozenges, a salt-water gargle, or chewing gum to help keep the throat moist.
• Give the voice as much complete rest as possible.
• Avoid whispering; whispering is harder on the vocal folds than normal speech.

Other causes of laryngitis include:

• Infections caused by bacteria or fungi
• Irritation of the throat caused by smoking
• Drying of the tissues lining the throat caused by asthma inhalers, overuse of decongestants, or antihistamines
• Exposure to dust, chemicals, smoke, fumes, or other irritating substances in a person's workplace
• High levels of alcohol consumption
• Air pollution
• Gastroesophageal reflux disease (GERD; a disorder in which acid from the stomach flows backward up the esophagus and into the throat, irritating the throat tissues.)
• Repeated episodes of sinus infection
• Throat cancer

In addition to a hoarse or faint voice, people with laryngitis may complain of soreness in the throat, a tickling sensation, a dry cough, difficulty breathing, or discomfort when swallowing food.

Diagnosis

Acute laryngitis is usually diagnosed by taking the patient's history—particularly recent exposure to colds or flu—and an examination of the throat and neck. The doctor will usually feel the outside of the neck for signs of swollen lymph glands and will look down the patient's throat using a mirror or with a device called a laryngoscope. If the patient has acute laryngitis, the vocal folds will look red, swollen, and covered with fluid secretions. Laboratory studies are not usually needed.

If the patient has chronic laryngitis, the doctor will examine him or her for signs of GERD or refer the patient to an otolaryngologist. Otolaryngologists are doctors who specialize in diagnosing disorders of the ears, nose, and throat. The patient may need some special examinations to evaluate the possibility of throat cancer.

Treatment

People can often treat acute laryngitis at home with some simple remedies (see sidebar). It is not usually necessary to take antibiotics for acute laryngitis, as several studies have shown that these drugs do not speed up the patient's recovery. If the laryngitis does not clear up after two weeks, however, the patient should have the throat checked again.

Chronic laryngitis caused by GERD is usually treated by drugs that lower the production of stomach acid, by changes in the patient's diet, and by raising the head of the bed during sleep. The laryngitis usually clears up once the abnormal backward flow of stomach acid into the throat stops.

Laryngitis caused by overuse of the voice is usually treated by complete vocal rest for several days. Even if the patient is a professional singer, cheerleader, or public speaker, trying to use the voice during an episode of laryngitis can make the condition worse.

Prognosis

Acute laryngitis caused by an infection usually clears up completely in about a week. The prognosis of chronic laryngitis depends on the cause of the condition. People with chronic laryngitis caused by GERD or by overuse of the voice will usually recover without complications if they follow the doctor's advice about diet and vocal rest. The prognosis of

throat cancer depends on the stage of the cancer at the time it is diagnosed. Fortunately, throat cancer is a very rare cause of laryngitis.

Prevention

Some measures can be taken to reduce the risk of getting laryngitis:

• Quitting smoking (or not starting in the first place) and avoiding secondhand smoke.
• Taking precautions against colds and flu; for many people, these measures include an annual flu shot.
• Avoiding the overuse of antihistamines or decongestants when treating a cold at home.
• Avoiding breathing irritating household cleansers and other chemicals.
• Avoiding overuse of the voice, including loud yelling or screaming.

The Future

Laryngitis is a common health problem that is likely to continue to be common, if only because it is so often associated with colds and other common respiratory ailments. Laryngitis related to occupational hazards is also likely to continue to be a common health problem.

SEE ALSO Asthma; Common cold; Gastroesophageal reflux disease; Influenza; Smoking; Sore throat

WORDS TO KNOW

Chronic: Recurrent or long-lasting.

Larynx: The medical name for the voice box located at the base of the throat.

Otolaryngologist: A doctor who specializes in diagnosing and treating diseases of the ears, nose, and throat.

Pitch: The highness or lowness of the voice or a musical note.

Vocal folds: Twin folds of mucous membrane stretched across the larynx. They are also known as vocal cords.

For more information

BOOKS

Beers, Mark J., ed. Merck Manual of Medical Information, 2nd home ed. Whitehouse Station, NJ: Merck Medical Laboratories, 2003.

WEBSITES

KidsHealth. Laryngitis. Available online at http://www.kidshealth.org/kid/ill_injure/sick/laryngitis.html (accessed April 19, 2008).

Mayo Clinic. Laryngitis. Available online at http://www.mayoclinic.com/health/laryngitis/DS00366/DSECTION=1 (accessed April 20, 2008).

University of Michigan Health System. “Laryngitis.” Adult Health Advisor, 2005. Available online at http://www.med.umich.edu/1libr/aha/aha_chronlar_crs.htm (accessed April 20, 2008).