From the Guidelines
Laryngitis is primarily caused by acute viral infections, such as parainfluenza, rhinovirus, influenza, and adenovirus, which are self-limited and resolve within 7 to 10 days irrespective of treatment. The most recent and highest quality study, published in 2018 1, supports this statement, emphasizing that dysphonia in most patients is caused by acute viral laryngitis, which is not a bacterial infection.
Causes of Laryngitis
- Viral infections, including parainfluenza, rhinovirus, influenza, and adenovirus, are the most common cause of laryngitis, as stated in the 2018 study 1.
- Upper respiratory infections can also produce symptoms of sore throat, fever, and globus sensation, altering voice quality and function.
- Other potential causes, although less common, include bacterial infections, vocal strain, allergies, gastroesophageal reflux disease (GERD), smoking, exposure to irritants or chemicals, and in rare cases, fungal infections.
Treatment and Management
- For viral laryngitis, symptoms typically resolve within 7 to 10 days with self-care measures such as voice rest, staying hydrated, using a humidifier, and avoiding irritants like smoke.
- Antibiotics may be prescribed if laryngitis is caused by a bacterial infection, but their routine empiric use is unwarranted, as emphasized in the 2018 study 1.
- For laryngitis caused by GERD, acid-reducing medications may help alleviate symptoms.
Important Considerations
- The misuse of antibiotics exposes patients and the healthcare system to unnecessary costs and risks, including side effects and the development of antibiotic resistance, as highlighted in the 2018 study 1.
- Persistent laryngitis lasting more than two weeks warrants medical attention, as it could indicate a more serious condition requiring specialized treatment.
From the Research
Causes of Laryngitis
- Acute laryngitis is most often caused by viral illnesses through direct inflammation of the vocal cords or from irritation due to postnasal drainage 2
- Bacterial infections, such as acute epiglottitis, can also cause dysphonia but typically have other systemic symptoms as well as respiratory distress 2, 3
- Chronic laryngitis is characterized by symptoms lasting more than 3 weeks and can be related to overuse or stress on the vocal cords resulting in nodules or polyps 2
- Individuals in certain occupations, such as singers, school teachers, and chemical workers, are at greater risk of chronic laryngitis 2
- Viral infections, such as varicella zoster infection of the larynx, can also cause laryngitis 4
- Postviral vagal neuropathy can cause chronic cough and is a diagnosis of exclusion 4
Types of Laryngitis
- Acute laryngitis: caused by viral or bacterial infections 2, 3
- Chronic laryngitis: caused by overuse or stress on the vocal cords, or by certain occupations 2
- Epiglottitis (supraglottic laryngitis): related to bacterial infections 3
- Subglottic laryngitis: related to viral infections 3