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Throat Infection

(Pharyngitis; Tonsillitis; Tonsillopharyngitis)


Alan G. Cheng

, MD, Stanford University

Reviewed/Revised Feb 2024
Topic Resources

Infections of the throat and/or tonsils are common, particularly among children.

  • Throat infections are usually caused by a virus but may be caused by bacteria such as streptococcal bacteria.

  • Symptoms include severe pain when swallowing and swollen, red tonsils.

  • The diagnosis is based on an examination of the throat.

  • If untreated, tonsillopharyngitis that is caused by bacteria may cause an abscess to form in the tonsils.

  • Taking analgesics relieves pain , and a streptococcal infection is treated with antibiotics.

  • Sometimes the tonsils have to be surgically removed.

The tonsils contain lymphoid tissue Components of the Immune System The immune system is designed to defend the body against foreign or dangerous invaders. Such invaders include Microorganisms (commonly called germs, such as bacteria, viruses, and fungi) Parasites... read more that is part of the body's immune defense system. The tonsils intercept infectious microorganisms that enter the nose and throat and sometimes cause infections of the tonsils and nearby throat tissue.

People who have had their tonsils removed can still get throat infections.

Causes of Throat Infection

In about one third of people, throat infections are caused by a bacterial infection. Group A streptococcus is the most common bacteria that causes strep throat Streptococcal Infections Streptococcal infections are caused by any one of several species of Streptococcus. These gram-positive, sphere-shaped (coccal) bacteria (see figure ) cause many disorders, including... read more ; strep throat usually occurs in children between age 5 and age 15. Strep throat is less common among children under age 3 and older adults.

Rarely, bacterial infections such as gonorrhea and diphtheria cause throat infections.

Symptoms of Throat Infection

People with a throat infection have severe pain when swallowing and usually speaking. The pain is sometimes also felt in the ears. Some people have fever, headache, and an upset stomach. The tonsils are red and swollen and sometimes have white patches on them. Lymph nodes in the neck may become swollen and tender.

In people who have frequent tonsil infections, the normal small pits in the tonsils sometimes become filled with white, hardened secretions that resemble tiny stones. These stones can trap odor-causing bacteria, causing chronic bad breath, and can predispose people to subsequent bouts of tonsillitis.

Diagnosis of Throat Infection

  • A doctor's evaluation

  • Sometimes tests to check for strep throat

Doctors recognize a throat infection by viewing the throat. However, because the throat often looks the same in viral infections and bacterial infections, it is difficult for doctors to know whether the cause is a viral or bacterial infection just by looking at the throat. However, people with a runny nose and cough are more likely to have a viral infection.

Because strep throat Streptococcal Infections Streptococcal infections are caused by any one of several species of Streptococcus. These gram-positive, sphere-shaped (coccal) bacteria (see figure ) cause many disorders, including... read more requires antibiotics, it must be identified. To test for it, doctors swab the person's throat and do tests to identify streptococcus bacteria. Often, doctors test most children but test adults only if they meet certain criteria, such as having white patches on the tonsils (tonsillar exudates), swollen and tender lymph nodes in the neck, fever, and no cough. However, not all experts agree on when testing should be done or even when antibiotics should be given.

Treatment of Throat Infection

  • Pain relievers (analgesics)

  • For strep throat, antibiotics

  • Sometimes surgical removal of the tonsils

Drinking plenty of fluids and resting are recommended. Gargling with warm salt water has often been recommended but has not been shown to help.

Analgesics given by mouth, such as acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs), often help reduce pain in people with a throat infection. Some doctors also give a single dose of dexamethasone (a corticosteroid), given by mouth or injection, if symptoms are severe. Dexamethasone may shorten the duration of symptoms and relieve pain, enabling people to eat more. It may also help lessen airway blockage caused by inflammation. However, some doctors do not use dexamethasone or any corticosteroid because corticosteroids can have harmful side effects.

Lozenges and sprays that contain ingredients such as benzocaine, phenol, or lidocaine can reduce pain, However, they have to be used repeatedly, and using too much can have harmful effects. Also, they often affect taste.

People with a strep infection are given an antibiotic, usually penicillin or amoxicillin..


People who have repeated streptococcal infections of their tonsils may need to have their tonsils removed (tonsillectomy).

Typically, it is children who need tonsillectomy. Doctors consider tonsillectomy if the child has any of the following:

Tonsillectomy is also done if doctors suspect cancer.

For adults, doctors do not use these specific criteria for when to do tonsillectomy. However, doctors may do tonsillectomy in adults who have severe bad breath due to tonsillar stones.

For both children and adults, doctors decide whether to recommend a tonsillectomy based on individual differences (such as the person's age, general health, and the ease with which they have recovered from previous infections.

There are numerous effective techniques for tonsillectomy. The aim is to completely or partially remove the tonsils. Doctors can use a scalpel or an electrocautery device, or they can destroy the tonsils using radio waves. These techniques cause very little bleeding. Occasionally, a wire and snare technique is used. With this technique, a surgeon lassos the tonsils and snips them off with a sharp wire. All of these techniques effectively relieve the airway blockage that is causing snoring and interrupted sleep as well as recurrent tonsillitis. Tonsils do not usually grow back.

After surgery, complications may occur.

Only a few people—adults more than children—have bleeding complications after a tonsillectomy. Bleeding typically occurs within 24 hours of surgery or after about 7 days. People who have bleeding after a tonsillectomy should go to a hospital.

The airway may become blocked, most frequently in children who are under 2 years old and who had severe obstructive sleep apnea and in people who have morbid obesity or neurologic disorders or had significant obstructive sleep apnea before surgery. Complications are usually more common and serious among young children.


Drugs Mentioned In This Article

Generic Name Select Brand Names
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
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
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
Castellani Paint, Chloraseptic, Chloraseptic Kids, Phenaseptic, Sore Throat
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, Ela-Max, GEN7T, Glydo, Gold Bond, LidaFlex, LidaMantle, 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, 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
Amoxil, Dispermox, Moxatag, Moxilin , Sumox, Trimox
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