Merck Manual

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Clarence T. Sasaki

, MD, Yale University School of Medicine

Last full review/revision Jul 2020| Content last modified Jul 2020
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Laryngitis is inflammation of the larynx, usually the result of a virus or overuse. The result is acute change in the voice, with decreased volume and hoarseness. Diagnosis is based on clinical findings. Laryngoscopy is required for symptoms persisting > 3 weeks. Viral laryngitis is self-limited. Other infectious or irritating causes may require specific treatment.

The most common cause of acute laryngitis is

  • Viral upper respiratory infection

Coughing-induced laryngitis may also occur in bronchitis, pneumonia, influenza, pertussis, measles, and diphtheria. Excessive use of the voice (especially with loud speaking or singing), allergic reactions, gastroesophageal reflux, bulimia, or inhalation of irritating substances (eg, cigarette smoke or certain aerosolized drugs) can cause acute or chronic laryngitis. Drugs can induce potentially life-threatening laryngeal edema, for example, as a side effect of angiotensin-converting enzyme (ACE) inhibitors. Bacterial laryngitis is extremely rare. Smoking can cause Reinke edema, which is a watery swelling of both vocal cords.

Symptoms and Signs

The most prominent symptom of laryngitis is usually

  • An unnatural change of voice

Volume is typically greatly decreased; some patients have aphonia. Hoarseness, a sensation of tickling, rawness, and a constant urge to clear the throat may occur. Symptoms vary with the severity of the inflammation.

Fever, malaise, dysphagia, and throat pain may occur in more severe infections. Laryngeal edema, although rare, may cause stridor and dyspnea.


  • Clinical evaluation

  • Sometimes indirect or direct laryngoscopy

Diagnosis of laryngitis is based on symptoms.

Indirect or direct flexible laryngoscopy is recommended for symptoms persisting > 3 weeks; findings in laryngitis include mild to marked erythema of the mucous membrane, which may also be edematous. With reflux, there is swelling of the inner lining of the larynx and redness of the arytenoids.

If a pseudomembrane is present, diphtheria is suspected.


  • Symptomatic treatment (eg, cough suppressants, voice rest, steam inhalations)

No specific treatment is available for viral laryngitis.

Cough suppressants, voice rest, and steam inhalations relieve symptoms and promote resolution of acute laryngitis. Smoking cessation and treatment of acute or chronic bronchitis may relieve laryngitis.

Depending on the presumed cause, specific treatments to control gastroesophageal reflux, bulimia, or drug-induced laryngitis may be beneficial.

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