Laryngitis

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Laryngitis
Laryngitis gastrica.jpg
Endoscopic image of an inflamed larynx caused by acid reflux
Pronunciation
Specialty Otorhinolaryngology
Symptoms Hoarse voice, fever, pain [1] [2]
DurationUsually less than 2 weeks [1]
CausesViral, trauma, bacterial [1]
Diagnostic method Based on symptoms, examination via laryngoscopy if concerns [1]
Differential diagnosis Epiglottitis, laryngeal cancer, croup [1]
TreatmentVoice rest, fluids [1]
FrequencyCommon [1]

Laryngitis is inflammation of the larynx (voice box). [1] Symptoms often include a hoarse voice and may include fever, cough, pain in the front of the neck, and trouble swallowing. [1] [2] Typically, these last under two weeks. [1]

Contents

Laryngitis is categorised as acute if it lasts less than three weeks and chronic if symptoms last more than three weeks. [1] Acute cases usually occur as part of a viral upper respiratory tract infection, [1] other infections and trauma such as from coughing are other causes. [1] Chronic cases may occur due to smoking, tuberculosis, allergies, acid reflux, rheumatoid arthritis, or sarcoidosis. [1] [3] The underlying mechanism involves irritation of the vocal cords. [2]

Concerning signs that may require further investigation include stridor, history of radiation therapy to the neck, trouble swallowing, duration of more than three weeks, and a history of smoking. [1] If concerning signs are present the vocal cords should be examined via laryngoscopy. [1] Other conditions that can produce similar symptoms include epiglottitis, croup, inhaling a foreign body, and laryngeal cancer. [1] [4]

The acute form generally resolves without specific treatment. [1] Resting the voice and sufficient fluids may help. [1] Antibiotics generally do not appear to be useful in the acute form. [5] The acute form is common while the chronic form is not. [1] The chronic form occurs most often in middle age and is more common in men than women. [6]

Signs and symptoms

The primary symptom of laryngitis is a hoarse voice. [7] :108 Because laryngitis can have various causes, other signs and symptoms may vary. [8] They can include

Voice quality

Aside from a hoarse-sounding voice, changes to pitch and volume may occur with laryngitis. Speakers may experience a lower or higher pitch than normal, depending on whether their vocal folds are swollen or stiff. [1] [9] They may also have breathier voices, as more air flows through the space between the vocal folds (the glottis), quieter volume [10] and a reduced range. [1]

Causes

Laryngitis Laryngitis.png
Laryngitis

Laryngitis can be infectious as well as noninfectious in origin. The resulting inflammation of the vocal folds results in a distortion of the sound produced there. [1] It normally develops in response to either an infection, trauma to the vocal folds, or allergies. [3] Chronic laryngitis may also be caused by more severe problems, such as nerve damage, sores, polyps, or hard and thick lumps (nodules) on the vocal cords. [11]

Acute

Viral

Bacterial

Fungal

  • Laryngitis caused by fungal infection is common but not frequently diagnosed according to a review by BMJ and can account for up to 10% of acute laryngitis cases. [1] Patients with both functioning and impaired immune systems can develop fungal laryngitis, which may develop as a result of recent antibiotic or inhaled corticosteroids use. [1] Certain strains of fungi that may cause laryngitis include; Histoplasma , Blastomyces , Candida (especially in immunocompromised persons), and Cryptococcus and Coccidioides .[ citation needed ]

Trauma

  • Often due to excessive use of the vocal folds such as excessive yelling, screaming, or singing. Though this often results in damage to the outer layers of the vocal folds, the subsequent healing may lead to changes in the physiology of the folds. [1] Another potential cause of inflammation may be overuse of the vocal cords. [12] [13] [14] [15] [16] Laryngeal trauma, including iatrogenic (caused by endotracheal intubation), can also result in inflammation of the vocal cords. [17]

Chronic

Allergies

  • Findings are unclear as to whether asthma may cause symptoms commonly associated with laryngitis. [1] Some researchers have posited that allergic causes of laryngitis are often misdiagnosed as being the result of acid reflux. [18]

Reflux

  • One possible explanation of chronic laryngitis is that inflammation is caused by gastro-oesophageal reflux, which causes subsequent irritation of the vocal folds. [19]

Autoimmune disorders

  • Approximately between 30 and 75% of persons with rheumatoid arthritis report symptoms of laryngitis. [1]
  • Symptoms of laryngitis are present in only 0.5–5% of people that have sarcoidosis. [1] According to a meta-analysis by Silva et al. (2007), this disease is often an uncommon cause of laryngeal symptoms and is frequently misdiagnosed as another voice disorder. [20]

Diagnosis

Diagnosis of different forms of acute laryngitis

Visual diagnosis

The larynx itself will often show erythema (reddening) and  edema  (swelling). This can be seen with laryngoscopy or stroboscopy (method depends on the type of laryngitis). [7] :108 Stroboscopy may be relatively normal or may reveal asymmetry, aperiodicity, and reduced mucosal wave patterns. [22]

Other features of the laryngeal tissues may include[ citation needed ]

Referral

Some signs and symptoms indicate the need for early referral. [1] These include

Differential diagnosis

Treatment

Treatment is often supportive in nature, and depends on the severity and type of laryngitis (acute or chronic). [1] General measures to relieve symptoms of laryngitis include behaviour modification, hydration and humidification. [1]

Vocal hygiene (care of the voice) is very important to relieve symptoms of laryngitis. Vocal hygiene involves measures such as: resting the voice, drinking sufficient water, reducing caffeine and alcohol intake, stopping smoking and limiting throat clearing. [1]

Acute laryngitis

In general, acute laryngitis treatment involves vocal hygiene, painkillers (analgesics), humidification, and antibiotics. [1] [5]

Viral

The suggested treatment for viral laryngitis involves vocal rest, pain medication, and mucolytics for frequent coughing. [7] Home remedies such as tea and honey may also be helpful. [1] Antibiotics are not used for treatment of viral laryngitis. [1] [23]

Bacterial

Antibiotics may be prescribed for bacterial laryngitis, especially when symptoms of upper respiratory infection are present. [7] However, the use of antibiotics is highly debated for acute laryngitis. This relates to issues of effectiveness, side effects, cost, and possibility of antibiotic resistance patterns. Overall, antibiotics do not appear to be very effective in the treatment of acute laryngitis. [5]

In severe cases of bacterial laryngitis, such as supraglottitis or epiglottitis, there is a higher risk of the airway becoming blocked. [7] An urgent referral should be made to manage the airway. [1] Treatment may involve humidification, corticosteroids, intravenous antibiotics, and nebulised adrenaline. [7]

Fungal

Fungal laryngitis can be treated with oral antifungal tablets and antifungal solutions. [1] [7] These are typically used for up to three weeks and treatment may need to be repeated if the fungal infection returns. [7]

Trauma

Laryngitis caused by excessive use or misuse of the voice can be managed through vocal hygiene measures.[ citation needed ]

Chronic laryngitis

Reflux

Laryngopharyngeal reflux treatment primarily involves behavioural management and medication. [1] [7] Behavioural management involves aspects such as

  • Wearing loose clothing
  • Eating smaller, more frequent meals
  • Avoiding certain foods (e.g. caffeine, alcohol, spicy foods) [7]

Anti-reflux medications may be prescribed for patients with signs of chronic laryngitis and hoarse voice. [24] If anti-reflux treatment does not result in a decrease of symptoms, other possible causes should be examined. [1] Over-the-counter medications for neutralizing acids (antacids) and acid suppressants (H-2 blockers) may be used. [7] Antacids are often short-acting and may not be sufficient for treatment. [7] Proton pump inhibitors are an effective type of medication. [7] These should only be prescribed for a set period of time, after which the symptoms should be reviewed. [1] Proton pump inhibitors do not work for everyone. A physical reflux barrier (e.g. Gaviscon Liquid) may be more appropriate for some. [1] Antisecretory medications can have several side-effects. [1]

When appropriate, anti-reflux surgery may benefit some individuals. [1]

Inflammatory

When treating allergic laryngitis, topical nasal steroids and immunotherapy have been found to be effective for allergic rhinitis. [7] Antihistamines may also be helpful, but can create a dryness in the larynx. [7] Inhaled steroids that are used for a long period can lead to problems with the larynx and voice. [7]

Autoimmune

Mucous membrane pemphigoid may be managed with medication (cyclophosphamide and prednisolone). [1]

Granulomatous

Sarcoidosis is typically treated with systemic corticosteroids. Less frequently used treatments include intralesional injections or laser resection. [1]

Prognosis

Acute

Acute laryngitis may persist, but will typically resolve on its own within two weeks. [1] Recovery is likely to be quick if the patient follows the treatment plan. [25] In viral laryngitis, symptoms can persist for an extended period, even when upper respiratory tract inflammation has been resolved. [23]

Chronic

Laryngitis that continues for more than three weeks is considered chronic. [1] If laryngeal symptoms last for more than three weeks, a referral should be made for further examination, including direct laryngoscopy. [1] The prognosis for chronic laryngitis varies depending on the cause of the laryngitis. [25]

Related Research Articles

<span class="mw-page-title-main">Sinusitis</span> Inflammation of the mucous membrane that lines the sinuses resulting in symptoms

Sinusitis, also known as rhinosinusitis, is inflammation of the mucous membranes that line the sinuses resulting in symptoms that may include thick nasal mucus, a plugged nose, and facial pain. Other signs and symptoms may include fever, headaches, a poor sense of smell, sore throat, a feeling that phlegm is oozing out from the back of the nose to the throat along with a necessity to clear the throat frequently and frequent attacks of cough.

<span class="mw-page-title-main">Larynx</span> Voice box, an organ in the neck of amphibians, reptiles, and mammals

The larynx, commonly called the voice box, is an organ in the top of the neck involved in breathing, producing sound and protecting the trachea against food aspiration. The opening of larynx into pharynx known as the laryngeal inlet is about 4–5 centimeters in diameter. The larynx houses the vocal cords, and manipulates pitch and volume, which is essential for phonation. It is situated just below where the tract of the pharynx splits into the trachea and the esophagus. The word 'larynx' comes from the Ancient Greek word lárunx ʻlarynx, gullet, throat.ʼ

<span class="mw-page-title-main">Reinke's edema</span> Medical condition

Reinke's edema is the swelling of the vocal cords due to fluid (edema) collected within the Reinke's space. First identified by the German anatomist Friedrich B. Reinke in 1895, the Reinke's space is a gelatinous layer of the vocal cord located underneath the outer cells of the vocal cord. When a person speaks, the Reinke's space vibrates to allow for sound to be produced (phonation). The Reinke's space is sometimes referred to as the superficial lamina propria.

<span class="mw-page-title-main">Cough</span> Sudden expulsion of air from the lungs as a reflex to clear irritants

A cough is a sudden expulsion of air through the large breathing passages which can help clear them of fluids, irritants, foreign particles and microbes. As a protective reflex, coughing can be repetitive with the cough reflex following three phases: an inhalation, a forced exhalation against a closed glottis, and a violent release of air from the lungs following opening of the glottis, usually accompanied by a distinctive sound.

<span class="mw-page-title-main">Pharyngitis</span> Inflammation of the back of the throat

Pharyngitis is inflammation of the back of the throat, known as the pharynx. It typically results in a sore throat and fever. Other symptoms may include a runny nose, cough, headache, difficulty swallowing, swollen lymph nodes, and a hoarse voice. Symptoms usually last 3–5 days, but can be longer depending on cause. Complications can include sinusitis and acute otitis media. Pharyngitis is a type of upper respiratory tract infection.

<span class="mw-page-title-main">Phlegm</span> Mucus produced by the respiratory system (excluding the nasal passages)

Phlegm is mucus produced by the respiratory system, excluding that produced by the throat nasal passages. It often refers to respiratory mucus expelled by coughing, otherwise known as sputum. Phlegm, and mucus as a whole, is in essence a water-based gel consisting of glycoproteins, immunoglobulins, lipids and other substances. Its composition varies depending on climate, genetics, and state of the immune system. Its color can vary from transparent to pale or dark yellow and green, from light to dark brown, and even to dark grey depending on the constituents. The body naturally produces about 1 quart of phlegm every day to capture and clear substances in the air and bacteria from the nose and throat.

<span class="mw-page-title-main">Croup</span> Respiratory infection often caused by a virus

Croup, also known as laryngotracheobronchitis, is a type of respiratory infection that is usually caused by a virus. The infection leads to swelling inside the trachea, which interferes with normal breathing and produces the classic symptoms of "barking/brassy" cough, inspiratory stridor and a hoarse voice. Fever and runny nose may also be present. These symptoms may be mild, moderate, or severe. Often it starts or is worse at night and normally lasts one to two days.

<span class="mw-page-title-main">Upper respiratory tract infection</span> Medical condition

An upper respiratory tract infection (URTI) is an illness caused by an acute infection, which involves the upper respiratory tract, including the nose, sinuses, pharynx, larynx or trachea. This commonly includes nasal obstruction, sore throat, tonsillitis, pharyngitis, laryngitis, sinusitis, otitis media, and the common cold. Most infections are viral in nature, and in other instances, the cause is bacterial. URTIs can also be fungal or helminthic in origin, but these are less common.

<span class="mw-page-title-main">Tonsillitis</span> Inflammation of the tonsils

Tonsillitis is inflammation of the tonsils in the upper part of the throat. It can be acute or chronic. Acute tonsillitis typically has a rapid onset. Symptoms may include sore throat, fever, enlargement of the tonsils, trouble swallowing, and enlarged lymph nodes around the neck. Complications include peritonsillar abscess (Quinsy).

<span class="mw-page-title-main">Post-nasal drip</span> Medical condition

Post-nasal drip (PND), also known as upper airway cough syndrome (UACS), occurs when excessive mucus is produced by the nasal mucosa. The excess mucus accumulates in the back of the nose, and eventually in the throat once it drips down the back of the throat. It can be caused by rhinitis, sinusitis, gastroesophageal reflux disease (GERD), or by a disorder of swallowing. Other causes can be allergy, cold, flu, and side effects from medications.

<span class="mw-page-title-main">Laryngeal papillomatosis</span> Medical condition

Laryngeal papillomatosis, also known as recurrent respiratory papillomatosis (RRP) or glottal papillomatosis, is a rare medical condition in which benign tumors (papilloma) form along the aerodigestive tract. There are two variants based on the age of onset: juvenile and adult laryngeal papillomatosis. The tumors are caused by human papillomavirus (HPV) infection of the throat. The tumors may lead to narrowing of the airway, which may cause vocal changes or airway obstruction. Laryngeal papillomatosis is initially diagnosed through indirect laryngoscopy upon observation of growths on the larynx and can be confirmed through a biopsy. Treatment for laryngeal papillomatosis aims to remove the papillomas and limit their recurrence. Due to the recurrent nature of the virus, repeated treatments usually are needed. Laryngeal papillomatosis is primarily treated surgically, though supplemental nonsurgical and/or medical treatments may be considered in some cases. The evolution of laryngeal papillomatosis is highly variable. Though total recovery may be observed, it is often persistent despite treatment. The number of new cases of laryngeal papillomatosis cases is approximately 4.3 cases per 100,000 children and 1.8 cases per 100,000 adults annually.

<span class="mw-page-title-main">Bogart–Bacall syndrome</span> Voice disorder caused by abuse or overuse of the vocal cords

Bogart–Bacall syndrome (BBS) is a voice disorder that is caused by abuse or overuse of the vocal cords.

A hoarse voice, also known as dysphonia or hoarseness, is when the voice involuntarily sounds breathy, raspy, or strained, or is softer in volume or lower in pitch. A hoarse voice can be associated with a feeling of unease or scratchiness in the throat. Hoarseness is often a symptom of problems in the vocal folds of the larynx. It may be caused by laryngitis, which in turn may be caused by an upper respiratory infection, a cold, or allergies. Cheering at sporting events, speaking loudly in noisy situations, talking for too long without resting one's voice, singing loudly, or speaking with a voice that is too high or too low can also cause temporary hoarseness. A number of other causes for losing one's voice exist, and treatment is generally by resting the voice and treating the underlying cause. If the cause is misuse or overuse of the voice, drinking plenty of water may alleviate the problems.

<span class="mw-page-title-main">Contact granuloma</span> Medical condition

Contact granuloma is a condition that develops due to persistent tissue irritation in the posterior larynx. Benign granulomas, not to be confused with other types of granulomas, occur on the vocal process of the vocal folds, where the vocal ligament attaches. Signs and symptoms may include hoarseness of the voice, or a sensation of having a lump in the throat, but contact granulomas may also be without symptoms. There are two common causes associated with contact granulomas; the first common cause is sustained periods of increased pressure on the vocal folds, and is commonly seen in people who use their voice excessively, such as singers. Treatment typically includes voice therapy and changes to lifestyle factors. The second common cause of granulomas is gastroesophageal reflux and is controlled primarily through the use of anti-reflux medication. Other associated causes are discussed below.

Vocal cord paresis, also known as recurrent laryngeal nerve paralysis or vocal fold paralysis, is an injury to one or both recurrent laryngeal nerves (RLNs), which control all intrinsic muscles of the larynx except for the cricothyroid muscle. The RLN is important for speaking, breathing and swallowing.

<span class="mw-page-title-main">Laryngopharyngeal reflux</span> Medical condition

Laryngopharyngeal reflux (LPR) is the retrograde flow of gastric contents into the larynx, oropharynx and/or the nasopharynx. LPR causes respiratory symptoms such as cough and wheezing and is often associated with head and neck complaints such as dysphonia, globus pharyngis, and dysphagia. LPR may play a role in other diseases, such as sinusitis, otitis media, and rhinitis, and can be a comorbidity of asthma. While LPR is commonly used interchangeably with gastroesophageal reflux disease (GERD), it presents with a different pathophysiology.

Vocal cord dysfunction (VCD) is a pathology affecting the vocal folds characterized by full or partial vocal fold closure causing difficulty and distress during respiration, especially during inhalation.

Throat irritation can refer to a dry cough, a scratchy feeling at the back of the throat, a sensation of a lumpy feeling, something stuck at the back of the throat, or possibly a feeling of dust in the throat. The symptoms are unpleasant and usually temporary, but occasionally signifies a more serious health issue, such as laryngitis.

<span class="mw-page-title-main">Otitis externa</span> Inflammation of the ear canal

Otitis externa, also called swimmer's ear, is inflammation of the ear canal. It often presents with ear pain, swelling of the ear canal, and occasionally decreased hearing. Typically there is pain with movement of the outer ear. A high fever is typically not present except in severe cases.

Chronic cough is long-term coughing, sometimes defined as more than several weeks or months. Generally a cough lasting for more than eight weeks for an adult would meet the clinical definition of a chronic cough; and for children this threshold is lower. The term can be used to describe the different causes related to coughing, the three main ones being upper airway cough syndrome, asthma and gastroesophageal reflux disease. It occurs in the upper airway of the respiratory system. Generally, a cough lasts around one to two weeks; however, chronic cough can persist for an extended period of time defined as six weeks or longer. People with chronic cough often experience more than one cause present. Due to the nature of the syndrome, the treatments used are similar; however, there are a subsequent number of treatments available, and the clinical management of the patients remains a challenge.

References

  1. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 Wood, John M.; Athanasiadis, Theodore; Allen, Jacqui (9 October 2014). "Laryngitis". BMJ. 349: g5827. doi:10.1136/bmj.g5827. ISSN   1756-1833. PMID   25300640. S2CID   216101435. Archived from the original on 13 November 2016. Retrieved 21 November 2016.
  2. 1 2 3 "Laryngitis - National Library of Medicine". PubMed Health. Archived from the original on 10 September 2017. Retrieved 9 November 2016.
  3. 1 2 Dworkin, James Paul (April 2008). "Laryngitis: Types, Causes, and Treatments". Otolaryngologic Clinics of North America. 41 (2): 419–436. doi:10.1016/j.otc.2007.11.011. PMID   18328379.
  4. Ferri, Fred F. (2016). Ferri's Clinical Advisor 2017: 5 Books in 1. Elsevier Health Sciences. p. 709. ISBN   9780323448383. Archived from the original on 10 November 2016.
  5. 1 2 3 Reveiz, L; Cardona, AF (23 May 2015). "Antibiotics for acute laryngitis in adults". Cochrane Database of Systematic Reviews. 2015 (5): CD004783. doi:10.1002/14651858.CD004783.pub5. PMC   6486127 . PMID   26002823.
  6. Dhingra, P. L.; Dhingra, Shruti (2014). Diseases of Ear, Nose and Throat (6 ed.). Elsevier Health Sciences. p. 292. ISBN   9788131236932. Archived from the original on 10 November 2016.
  7. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Colton, Raymond H.; Casper, Janina K.; Leonard, Rebecca (2011). Understanding Voice Problems (4th ed.). Baltimore, MD: Lippincott Williams & Wilkins. pp. 308–309. ISBN   978-1-60913-874-5.
  8. Verdolini, Katherine; Rosen, Clark A.; Branksi, Ryan C., eds. (2006). Classification Manual of Voice Disorders-I. American Speech-Language-Hearing Association. Mahwah, N.J: Lawrence Erlbaum.
  9. Takahashi, H.; Koike, Y. (1976). "Some perceptual dimensions and acoustical correlates of pathologic voices". Acta Oto-Laryngologica Supplementum (338): 1–24.
  10. Shipp, Thomas; Huntington, Dorothy A. (1 November 1965). "Some Acoustic and Perceptual Factors in Acute-Laryngitic Hoarseness". Journal of Speech and Hearing Disorders. 30 (4): 350–9. doi:10.1044/jshd.3004.350. ISSN   0022-4677. PMID   5835492.
  11. Ferri, Fred F. (2016). Ferri's Clinical Advisor 2017: 5 Books in 1. Elsevier Health Sciences. p. 709. ISBN   9780323448383.[ verification needed ]
  12. Ferri, Fred F. (2016). Ferri's Clinical Advisor 2017: 5 Books in 1. Elsevier Health Sciences. p. 709. ISBN   9780323448383.[ verification needed ]
  13. Reveiz, L; Cardona, AF (23 May 2015). "Antibiotics for acute laryngitis in adults". The Cochrane Database of Systematic Reviews. 2015 (5): CD004783. doi:10.1002/14651858.CD004783.pub5. PMC   6486127 . PMID   26002823.[ verification needed ]
  14. Dhingra, P. L.; Dhingra, Shruti (2014). Diseases of Ear, Nose and Throat (6 ed.). Elsevier Health Sciences. p. 292. ISBN   9788131236932.[ verification needed ]
  15. Colton, Raymond H.; Casper, Janina K.; Leonard, Rebecca (2011). Understanding Voice Problems: A Physiological Perspective for Diagnosis and Treatment (4th ed.). Baltimore: Lippincott Williams & Wilkins. p. 108. ISBN   978-1609138745.[ verification needed ]
  16. Verdolini, Katherine; Rosen, Clark A.; Branksi, Ryan C., eds. (2006). Classification Manual of Voice Disorders-I. American Speech-Language-Hearing Association. Mahwah, N.J: Lawrence Erlbaum.[ verification needed ]
  17. Rieger, A.; Hass, I.; Gross, M.; Gramm, HJ; Eyrich, K. (1996). "Intubation trauma of the larynx--a literature review with special reference to arytenoid cartilage dislocation". Anasthesiol Intensivmed Notfallmed Schmerzther. 31 (5): 281–287. doi:10.1055/s-2007-995921. PMID   8767240. S2CID   58424810.
  18. Brook, Christopher; Platt, Michael; Reese, Stephen; Noordzij, Pieter (January 2016). "Utility of Allergy Testing in Patients with Chronic Laryngopharyngeal Symptoms: Is It Allergic Laryngitis?". Otolaryngology–Head and Neck Surgery. 154 (1): 41–45. doi:10.1177/0194599815607850. PMID   26428475. S2CID   24593040.
  19. Joniau, Sander; Bradshaw, Anthony; Esterman, Adrian; Carney, A. Simon (May 2007). "Reflux and laryngitis: A systematic review". Otolaryngology–Head and Neck Surgery. 136 (5): 686–692. doi: 10.1016/j.otohns.2006.12.004 . PMID   17478199. S2CID   24123158.
  20. Silva, Leonardo; Damrose, Edward; Bairao, Fernanda; Nina, Mayra; Junior, James; Costa, Henrique (June 2008). "Infectious granulomatous laryngitis: a retrospective study of 24 cases". European Archives of Oto-Rhino-Laryngology. 265 (6): 675–680. doi:10.1007/s00405-007-0533-4. PMID   18060554. S2CID   19082413.
  21. 1 2 3 House, SA (December 2017). "Hoarseness in Adults". Am Fam Physician. 11 (11): 720–728. PMID   29431404.
  22. 1 2 3 4 5 Gupta G, Mahajan K (2020). "Acute Laryngitis". Statpearls. PMID   30521292. CC-BY icon.svg Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License.
  23. 1 2 Dominguez, L. M.; Simpson, C. B. (December 2015). "Viral laryngitis". Current Opinion in Otolaryngology & Head and Neck Surgery. 23 (6): 454–458. doi:10.1097/moo.0000000000000203. PMID   26397458. S2CID   10954996.
  24. Schwartz, Seth R.; Cohen, Seth M.; Dailey, Seth H.; Rosenfeld, Richard M.; Deutsch, Ellen S.; Gillespie, M. Boyd; Granieri, Evelyn; Hapner, Edie R.; Kimball, C. Eve (1 September 2009). "Clinical Practice Guideline Hoarseness (Dysphonia)". Otolaryngology–Head and Neck Surgery. 141 (3 suppl): S1–S31. doi: 10.1016/j.otohns.2009.06.744 . ISSN   0194-5998. PMID   19729111. S2CID   14655786.
  25. 1 2 Jonas, Nico (2007). "Laryngitis Management". Journal of Modern Pharmacy. 14 (5): 44.