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Sore Throat


Marvin P. Fried

, MD, Montefiore Medical Center, The University Hospital of Albert Einstein College of Medicine

Reviewed/Revised May 2023
Topic Resources

Sore throat is pain in the posterior pharynx that occurs with or without swallowing. Pain can be severe; many patients refuse oral intake.

Etiology of Sore Throat

Sore throat results from infection; the most common cause is

  • Tonsillopharyngitis

Rarely, an abscess or epiglottitis is involved; although uncommon, these disorders are of particular concern because they may compromise the airway.



Tonsillopharyngitis is predominantly a viral infection; a lesser number of cases are caused by bacteria.

The respiratory viruses Overview of Viral Respiratory Infections Viral infections commonly affect the upper or lower respiratory tract. Although respiratory infections can be classified by the causative virus (eg, influenza), they are generally classified... read more (rhinovirus, adenovirus, the influenza virus, coronavirus, respiratory syncytial virus) are the most common viral causes, but occasionally Epstein-Barr virus Infectious Mononucleosis Infectious mononucleosis is caused by Epstein-Barr virus (EBV, human herpesvirus type 4) and is characterized by fatigue, fever, pharyngitis, and lymphadenopathy. Fatigue may persist weeks or... read more Infectious Mononucleosis (the cause of mononucleosis), herpes simplex Herpes Simplex Virus (HSV) Infections Herpes simplex viruses (human herpesviruses types 1 and 2) commonly cause recurrent infection affecting the skin, mouth, lips, eyes, and genitals. Common severe infections include encephalitis... read more Herpes Simplex Virus (HSV) Infections , cytomegalovirus Cytomegalovirus (CMV) Infection Cytomegalovirus (CMV, human herpesvirus type 5) can cause infections that have a wide range of severity. A syndrome of infectious mononucleosis that lacks severe pharyngitis is common. Severe... read more , HIV Human Immunodeficiency Virus (HIV) Infection Human immunodeficiency virus (HIV) infection results from 1 of 2 similar retroviruses (HIV-1 and HIV-2) that destroy CD4+ lymphocytes and impair cell-mediated immunity, increasing risk of certain... read more Human Immunodeficiency Virus (HIV) Infection (as a primary infection), or coronavirus SARS-CoV-2 (the cause of COVID-19 COVID-19 COVID-19 is a respiratory illness caused by the novel coronavirus SARS-CoV-2. Infection may be asymptomatic or have symptoms ranging from mild upper respiratory symptoms to acute respiratory... read more ) is involved.

The main bacterial cause of sore throat is group A beta-hemolytic streptococci (GABHS Streptococcal Infections Streptococci are gram-positive aerobic organisms that cause many disorders, including pharyngitis, pneumonia, wound and skin infections, sepsis, and endocarditis. Symptoms vary with the organ... read more Streptococcal Infections ), which, although estimates vary, causes perhaps 10 to 25% of all sore throats in adults and slightly more in children. GABHS is a concern because serious poststreptococcal sequelae (eg, rheumatic fever, glomerulonephritis, abscess) may occur.



Epiglottitis Epiglottitis Epiglottitis is a rapidly progressive bacterial infection of the epiglottis and surrounding tissues that may lead to sudden respiratory obstruction and death. Symptoms include severe sore throat... read more Epiglottitis , perhaps better termed supraglottitis, used to occur primarily in children and usually was caused by Haemophilus influenzae type B (HiB). Now, because of widespread childhood vaccination against HiB, supraglottitis/epiglottitis has been almost eradicated in children; more cases occur in adults. Causal organisms in children and adults include Streptococcus pneumoniae, Staphylococcus aureus, nontypeable H. influenzae, Haemophilus parainfluenzae, beta-hemolytic streptococci, Branhamella catarrhalis, and Klebsiella pneumoniae. HiB is still a cause in adults and unvaccinated children.

Evaluation of Sore Throat


History of present illness should note the duration and severity of sore throat.

Review of systems should seek important associated symptoms, such as runny nose, cough, and difficulty swallowing, speaking, or breathing. The presence and duration of any preceding weakness and malaise (suggesting mononucleosis) are noted.

Past medical history should seek history of previous documented mononucleosis (recurrence is highly unlikely). Social history should include inquiring about close contact with people with documented GABHS infection, risk factors for gonorrhea transmission (eg, recent oral-genital sexual contact), and risk factors for HIV acquisition (eg, unprotected intercourse, multiple sex partners, IV drug abuse).

Physical examination

General examination should note fever and signs of respiratory distress, such as tachypnea, dyspnea, stridor, and, in children, the tripod position (sitting upright, leaning forward with neck hyperextended and jaw thrust forward).

During direct pharyngeal examination, erythema, exudates, and any signs of swelling around the tonsils or retropharyngeal area should be noted. Whether the uvula is in the midline or appears pushed to one side should also be noted.

If supraglottitis/epiglottitis is suspected and if patients (particularly children) have stridor, pharyngeal examination should be done cautiously because it, particularly when a tongue blade is inserted, may trigger complete airway obstruction. Ideally, examination should be done in an operating room and with a flexible fiberoptic laryngoscope,. Adults with no respiratory distress may be examined but also with care.

Red flags

The following findings in patients with a sore throat are of particular concern:

  • Stridor or other sign of respiratory distress

  • Drooling

  • Muffled, “hot potato” voice

  • Visible bulge in the pharynx

Interpretation of findings

With supraglottitis/epiglottitis, severe throat pain and dysphagia begin abruptly, usually with no preceding upper respiratory infection (URI) symptoms. Children often drool and have signs of toxicity. Sometimes (more often in children), patients have respiratory manifestations, with tachypnea, dyspnea, stridor, and sitting in the tripod position. If examined, the pharynx almost always appears unremarkable.

Pharyngeal abscess and tonsillopharyngitis may cause pharyngeal erythema, exudate, or both. However, some findings are more likely to occur in one condition or the other:

  • Pharyngeal abscess: Muffled, “hot potato” voice (speaking as if a hot object is being held in the mouth) and visible focal swelling in the posterior pharyngeal area (often with deviation of the uvula)

  • Tonsillopharyngitis: Often URI symptoms (eg, runny nose, cough)

Although tonsillopharyngitis is easily recognized clinically, its cause is not. Manifestations of viral and GABHS Streptococcal Infections Streptococci are gram-positive aerobic organisms that cause many disorders, including pharyngitis, pneumonia, wound and skin infections, sepsis, and endocarditis. Symptoms vary with the organ... read more Streptococcal Infections infection overlap significantly, although URI symptoms are more common with a viral cause. In adults, clinical criteria that increase suspicion of GABHS as a cause include

  • Tonsillar exudate

  • Tender lymphadenopathy

  • Fever or history of fever

  • Absence of cough

Adults with 1 or no criteria may reasonably be presumed to have viral illness. If ≥ 2 criteria are present, the likelihood of GABHS is high enough to warrant testing (1 Reference Sore throat is pain in the posterior pharynx that occurs with or without swallowing. Pain can be severe; many patients refuse oral intake. Sore throat results from infection; the most common... read more Reference ) but probably not high enough to warrant antibiotics, but this decision needs to be patient-specific (ie, threshold for testing and treatment may be lower in those at risk because of diabetes or immunocompromise). In children, testing usually is done. Although this approach is reasonable, not all experts agree on when to test for GABHS and when antibiotic treatment is indicated.

Rarer causes of tonsillopharyngitis should be considered when the following are present:


If supraglottitis/epiglottitis is considered possible after evaluation, specific testing is required. Patients who do not appear seriously ill and have no respiratory symptoms may have plain lateral neck x-rays to look for edematous epiglottis. However, these x-rays are subject to false-positive interpretation because patient positioning may be imperfect (not a perfectly lateral view) or the x-ray is taken during expiration. Also, a child who appears seriously ill or has stridor or any other respiratory symptoms should not be transported to the x-ray suite. Such patients (and those with positive or equivocal x-ray findings) should usually have flexible fiberoptic laryngoscopy. (CAUTION: Examination of the pharynx and larynx may precipitate complete respiratory obstruction in children, and the pharynx and larynx should not be directly examined except in the operating room, where the most advanced airway intervention is available.)

Pearls & Pitfalls

  • If epiglottitis is considered, directly examine a child's pharynx only in the operating room to minimize the risk of complete airway obstruction.

Many abscesses are managed clinically, but if location and extent are unclear, immediate CT of the neck should be done.

In tonsillopharyngitis, throat culture is the most reliable way to differentiate viral infection from GABHS. To balance timeliness of diagnosis, cost, and accuracy, one strategy in children is to do a rapid strep screen in the office and treat if positive, and if negative, send a formal culture to a laboratory for testing. In adults, because other bacterial pathogens may be involved, throat culture for all bacterial pathogens is appropriate for those meeting clinical criteria described previously (tonsillar exudate, tender lymphadenomegaly, fever or history of fever, absence of cough).

Testing for mononucleosis, gonorrhea, or HIV infection is done only when clinically suspected.


  • 1. Fine AM, Nizet V, Mandl KD: Large-scale validation of the Centor and McIsaac scores to predict group A streptococcal pharyngitis. Arch Intern Med 172 (11):847–852, 2012. doi:10.1001/archinternmed.2012.950

Treatment of Sore Throat

Specific conditions are treated. Patients with severe symptoms of tonsillopharyngitis may be started on a broad-spectrum antibiotic (eg, amoxicillin/clavulanate) pending culture results.

Symptomatic treatments such as warm saltwater gargles and topical anesthetics (eg, benzocaine, lidocaine, dyclonine) may help temporarily relieve pain in tonsillopharyngitis, but patients should be instructed to avoid doses of topical anesthetics that result in toxicity. Patients in severe pain (even from tonsillopharyngitis) may require short-term use of opioids, preferably in liquid preparations.

Corticosteroids (eg, dexamethasone, 10 mg IM) are occasionally used—for example, for tonsillopharyngitis that appears to pose a risk of airway obstruction (eg, due to mononucleosis) or very severe tonsillopharyngitis symptoms.

Key Points

  • Most sore throats are caused by viral tonsillopharyngitis.

  • It is difficult to clinically distinguish viral from bacterial causes of tonsillopharyngitis.

  • Abscess and epiglottitis are rare but serious causes.

  • Suspect epiglottitis if patients have a severe sore throat and a normal-appearing pharynx.

Drugs Mentioned In This Article

Drug Name Select Trade
Amoxil, Dispermox, Moxatag, Moxilin , Sumox, Trimox
Advocate Pain Relief Stick, Americaine, Anbesol, Anbesol Baby , Anbesol Jr , Banadyne-3, Benzodent, Benz-O-Sthetic, Boil-Ease, Cepacol Sensations, Chloraseptic, Comfort Caine , Dry Socket Remedy, Freez Eez, HURRICAINE, HURRICAINE ONE, Little Remedies for Teethers, Monistat Care, Orabase, OraCoat CankerMelts, Orajel, Orajel Baby, Orajel Denture Plus, Orajel Maximum Strength, Orajel P.M., Orajel Protective, Orajel Severe Pain, Orajel Swabs, Orajel Ultra, Oral Pain Relief , Oticaine , Otocain, Outgro, Pinnacaine, Pro-Caine, RE Benzotic, Topex, Topicale Xtra, Zilactin-B
7T Lido, Akten , ALOCANE, ANASTIA, AneCream, Anestacon, Aspercreme with Lidocaine, AsperFlex, Astero , BenGay, Blue Tube, Blue-Emu, CidalEaze, DermacinRx Lidocan III, DermacinRx Lidogel, DermacinRx Lidorex, DERMALID, Dologesic, Ela-Max, GEN7T, Glydo, Gold Bond, LidaFlex, LidaMantle, Lido King Maximum Strength, Lidocan, Lidocare, Lidoderm, LidoDose, LidoDose Pediatric, Lidofore, LidoHeal-90, LIDO-K , LidoLite, Lidomar , Lidomark, LidoPure, LidoReal-30, LidoRx, Lidosense 4 , Lidosense 5, Lidosol, Lidosol-50, LIDO-SORB, Lidotral, Lidovix L, LIDOZION, Lidozo, LMX 4, LMX 4 with Tegaderm, LMX 5, LTA, Lubricaine For Her, Lydexa, Moxicaine, Numbonex, ReadySharp Lidocaine, RectaSmoothe, RectiCare, Salonpas Lidocaine, Senatec, Solarcaine, SUN BURNT PLUS, Tranzarel, Xyliderm, Xylocaine, Xylocaine Dental, Xylocaine in Dextrose, Xylocaine MPF, Xylocaine Topical, Xylocaine Topical Jelly, Xylocaine Topical Solution, Xylocaine Viscous, Zilactin-L, Zingo, Zionodi, ZTlido
AK-Dex, Baycadron, Dalalone, Dalalone D.P, Dalalone L.A, Decadron, Decadron-LA, Dexabliss, Dexacort PH Turbinaire, Dexacort Respihaler, DexPak Jr TaperPak, DexPak TaperPak, Dextenza, DEXYCU, DoubleDex, Dxevo, Hemady, HiDex, Maxidex, Ocu-Dex , Ozurdex, ReadySharp Dexamethasone, Simplist Dexamethasone, Solurex, TaperDex, ZCORT, Zema-Pak, ZoDex, ZonaCort 11 Day, ZonaCort 7 Day
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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