What is tonsillitis?

Tonsillitis is inflammation of the tonsils caused by infection with viruses or bacteria. Common symptoms include a sore throat, swollen tonsils and lymph nodes, fever and difficulty swallowing.

Bacteria

Microscopic, single-celled organisms with DNA but no definite nucleus. Bacteria are the cause of many human diseases.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

What are tonsils?

Tonsils are lumps of tissue located on each side in the throat. They help to fight infections by clearing the viruses and bacteria that are breathed in or swallowed. Usually the tonsils do their job well, but sometimes the tonsils themselves can become infected, known as tonsillitis.

The tonsils start off small during the first year of life and then grow to their largest size between the ages of about 4-7 years. After this point, they tend to shrink as other areas of the immune system become stronger. For this reason, the chance of developing tonsillitis decreases with adulthood, although some adults may be prone to ongoing or repeated infections.

Healthy tonsils compared to red, swollen tonsils affected by tonsillitis.Red and swollen tonsils as seen in tonsillitis. 

Bacteria

Microscopic, single-celled organisms with DNA but no definite nucleus. Bacteria are the cause of many human diseases.

Causes

Most cases of tonsillitis are caused by a virus, such as a rhinovirus (common cold), influenza virus (the flu), enterovirus (hand, foot and mouth disease) or parainfluenza virus (croup). A small number of cases are caused by an infection of the throat with group A Streptococcus bacteria (streptococcal sore throat) that spreads to the tonsils.

Tonsillitis is spread by breathing in droplets of fluid that have been sneezed or coughed by an infected person.

Bacteria

Microscopic, single-celled organisms with DNA but no definite nucleus. Bacteria are the cause of many human diseases.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

Virus

A microscopic infectious agent that replicates itself only within cells of living hosts; a piece of nucleic acid (DNA or RNA) wrapped in a protein coat.

Risk factors

Risk factors that increase the likelihood of developing tonsillitis include:

  • Age - being a school-age or teenage child;
  • Exposure to a family or household member who has the condition;
  • Crowded environments, such as a day-care center or school;
  • A personal or family history of tonsillitis, and;
  • Being prone to the common cold.

Types

Tonsillitis is sometimes referred to as 'acute', 'chronic' or 'recurrent', depending on the length and pattern of symptoms.

  • Acute tonsillitis - generally clears within a week without any complications;
  • Chronic tonsillitis - an ongoing infection that may result in enlargement of the tonsils and an extended period of feeling tired and unwell, and;
  • Recurrent tonsillitis - multiple infections of acute tonsillitis within one year, possibly leading to severe enlargement and changes in the structure of the tonsils.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

Signs and symptoms

Common signs and symptoms of tonsillitis include:

  • Sore throat (pharyngitis);
  • Fever and chills;
  • Redness, swelling or white patches inside the throat;
  • Swollen lymph nodes (sometimes referred to incorrectly as 'glands') in the neck;
  • Pain when swallowing or talking;
  • Bad breath, and;
  • Pain in the ears.

If the flu virus is the cause of tonsillitis, additional symptoms may include a cough, runny nose and aching muscles.

Man with red, inflamed tonsils and swollen lymph nodes from tonsillitis.Common symptoms of tonsillitis are swollen lymph nodes, and red and white patches in the throat. 

Virus

A microscopic infectious agent that replicates itself only within cells of living hosts; a piece of nucleic acid (DNA or RNA) wrapped in a protein coat.

Methods for diagnosis

To diagnose tonsillitis, your doctor may look closely inside your throat, feel your neck, take your temperature and/or perform a throat swab.

During a throat swab, the throat and tonsils are gently rubbed with a sterile cotton swab, to collect a sample for laboratory testing. Laboratory testing can help identify the type of virus or bacteria that is causing tonsillitis, however it can take several days to get a result. A more helpful, immediate test that uses a throat swab, known as rapid antigen detection test (RADT), can help diagnose streptococcal sore throat, which assists your doctor in deciding whether to prescribe antibiotics. A blood sample can also help rule out other potential causes of a sore throat, such as mononucleosis.

Doctor swabbing the throat of a male patient.A throat swab procedure. 

Bacteria

Microscopic, single-celled organisms with DNA but no definite nucleus. Bacteria are the cause of many human diseases.

Virus

A microscopic infectious agent that replicates itself only within cells of living hosts; a piece of nucleic acid (DNA or RNA) wrapped in a protein coat.

Types of treatment

Treatments for tonsillitis aim to relieve pain, shorten the duration of illness, limit spread of infection and reduce the risk of complications. With these aims in mind, your doctor may prescribe one or more of the following options:

Self care

To relieve pain and fever, your doctor may suggest over-the-counter pain-relief medications, such as acetaminophen and ibuprofen (but not aspirin in children, due to the risk of Reye's syndrome). Similarly, saltwater gargles, soothing liquids and medicated lozenges that cool or numb the throat may be helpful. Water and rest may also be recommended to boost your immune system's natural response against infection.

Antibiotics

Most cases of tonsillitis clear on their own within a week, without the need for antibiotics. However, if streptococcal sore throat or another bacterial infection is confirmed, your doctor may prescribe antibiotics to reduce the risk of complications and prevent further spread of the condition. The most common antibiotic for tonsillitis is oral penicillin (if you are not allergic to penicillin), which is usually taken for several days. If you are allergic to penicillin, alternative antibiotics can be prescribed. Symptoms usually begin to improve within a day or two of starting treatment.

Also, antibiotics may be given as a precaution for particular individuals with a sore throat, if they are at increased risk of developing complications of streptococcal sore throat (see 'Potential complications'). These people include:

  • Aboriginal and Torres Strait Islanders between the ages of 2-25 years old who live in communities at high risk of rheumatic fever;
  • People with heart problems caused by rheumatic fever, and;
  • People with scarlet fever.

Surgery

If tonsillitis is recurrent, causes complications and/or leads to chronically enlarged tonsils which cause breathing difficulties or other issues, your doctor may provide a referral to discuss tonsil surgery with an ear, nose and throat (ENT) specialist. Surgery involves removal of both tonsils (tonsillectomy).

Tonsillectomy

This is a very common procedure with numerous different techniques for removing the tonsils. It can be performed for a variety of reasons, but the most common reason is recurrent tonsillitis. It is performed under a general anesthetic, with most individuals allowed to go home on the same day, but after a period of recovery. Occasionally, an overnight stay may be required. Most people recover fully within four weeks.

In children, tonsillectomy can commonly be combined with removal of the adenoids (known as adenoidectomy), which are also infection-fighting tissues at the back of the nose.

Following the procedure, regular pain-relief medications (not aspirin), plenty of fluids and food as tolerated are recommended. Some individuals can find this a potentially painful experience, but the pain generally settles with medications and rest. Avoiding strenuous physical activities for the first few weeks after the procedure is advisable.

Like all surgeries, tonsillectomy is associated with the potential risks. The main risks are bleeding, pain and infection. Bleeding following the procedure can be potentially life threatening, therefore it is important to seek prompt medical attention if this occurs.

General anesthetic

An anesthetic given to a person to put them to sleep while having an operation or medical procedure. Afterwards, the person regains consciousness and usually has no memory of the procedure. A general anesthetic is given in hospital by a specialist called an anesthetist.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

Potential complications

Complications related to tonsillitis are rare and mainly relate to streptococcal sore throat.

Streptococcal sore throat

If left untreated, the bacteria (group A Streptococcus bacteria) can spread and infect the following areas:

In a few cases, the body's immune system, in trying to remove the bacteria, can lead to inflammation in other areas of the body, including the joints, heart, kidney and skin. It gives rise to the following conditions:

Rheumatic fever

Rheumatic fever refers to widespread inflammation in the body, following untreated strep throat. It usually occurs about 2-4 weeks after the sore throat. The body's immune system, in attempting to fight off the bacteria, mistakenly attacks the various parts of the body. Commonly, joints, skin, heart and brain can be affected. While rheumatic fever leaves no lasting damage to the brain, joints or skin, it can cause permanent damage to the heart, known as rheumatic heart disease (see below).

Rheumatic heart disease

Rheumatic heart disease is permanent damage to the heart, following rheumatic fever. Various structures of the heart can be damaged by inflammation, including the muscle, lining or valves. It can lead to heart failure and sometimes the need for heart surgery.

Post-streptococcal glomerulonephritis

In a similar manner to rheumatic fever, the body's immune system damages the kidneys, leading to kidney disease. It generally occurs around 1-3 weeks after the sore throat.

Symptoms of post-streptococcal glomerulonephritis usually include blood in the urine, a puffy face and swollen feet and ankles. However, it usually clears on its own within a week without causing any lasting damage.

Scarlet fever

Scarlet fever occurs typically in children and shows up as a characteristic rough, red rash that starts on the neck and chest, before it spreads over the body. It is due to a poison released by the bacteria that cause streptococcal sore throat. It can start as early as 1-2 days after the onset of the sore throat. In the past, scarlet fever was considered to be a serious childhood disease. However, it is now treated with antibiotics.

Quinsy

Bacterial infections can also spread deep into the tissues surrounding the tonsils, leading to a collection of pus beside the tonsil, known as a peritonsillar abscess or quinsy. If left untreated, quinsy can cause extreme pain and difficulty sleeping, swallowing and breathing. This condition can occur in anyone, but usually affects teenagers and young adults. It is treated with a combination of antibiotics and drainage of pus from the abscess.

Bacteria

Microscopic, single-celled organisms with DNA but no definite nucleus. Bacteria are the cause of many human diseases.

Infection

Entry into the body of microorganisms that can reproduce and cause disease.

Pus

A bodily fluid that is the result of an inflammatory response at an infection site. Its color can range from whitish to yellow to green, depending on the composition. Pus is mainly composed of dead bacteria, white blood cells and cellular debris.

Prognosis

Although tonsillitis can be uncomfortable and painful, antibiotics are usually not required. Most people make a full recovery within about one week.

Recurrent symptoms or chronically enlarge tonsils may benefit from tonsillectomy.

Prevention

Avoiding contact with people who have symptoms of a cold, flu or sore throat may prevent tonsillitis. If contact cannot be completely avoided, regularly washing your hands and not sharing food, drinks or personal items with infected individuals may reduce the likelihood of developing tonsillitis.

Teaching children good hygiene habits, such as washing their hands and covering their mouth when coughing or sneezing, may help to limit the spread of tonsillitis. Seasonal flu vaccinations may also prevent the spread of viral tonsillitis, particularly in children, the elderly and people with a weakened immune system.

When tonsillitis does occur, staying at home and keeping children away from organized activities is recommended.

FAQ Frequently asked questions