Southern Cross Medical Library

Southern Cross Medical Library

Tonsillitis is the inflammation of the tonsils caused by bacterial or viral infection. Typical symptoms are sore throat, swollen tonsils, difficulty swallowing, fever, and swollen glands in the neck.

Tonsillitis occurs mainly in children, but rarely in children less than two years of age. Treatment will depend on whether the cause is bacterial or viral. Surgical removal of the tonsils (tonsillectomy) may be recommended in some cases.


The tonsils are two small rounded masses of tissue that can be seen in the back of the throat. They are made of tissue similar to the lymph glands and are part of the immune system.

The tonsils are thought to help protect the body from infection during the first year of life but are not essential for immune function in later life. There is no evidence that tonsillectomy reduces a person’s immunity.

The majority of tonsillitis cases are caused by viruses, with only 15–30% of cases caused by bacteria.

Many different viruses can cause viral tonsillitis, including cold and flu viruses, glandular fever, measles virus and cytomegalovirus. Most cases of bacterial tonsillitis are associated with the bacteria that causes strep throat.

Tonsillitis is contagious if the cause is bacterial, and may be contagious if the cause is viral and a person hasn't previously been exposed to that particular virus. In both cases, steps to prevent its spread should be taken.

Signs and symptoms

A sore throat is often the first sign of a cold and may get better after a day or two; other cold symptoms such as a runny nose and congestion may follow the sore throat. The primary symptom of tonsillitis is a moderate to severe sore throat lasting longer than 2 days and involves inflammation of the tonsils. Other symptoms of tonsillitis may include:

  • Difficult or painful swallowing
  • Swollen and tender glands (lymph nodes) on the sides of the neck
  • Fever and chills
  • Stomach upset or pain
  • Enlarged and reddened tonsils with spots of white/yellow pus
  • Mouth breathing, noisy breathing, and/or snoring (due to enlarged tonsils blocking the airways).

Symptoms of tonsillitis usually resolve after three to four days but may last up to two weeks, even with treatment.


The bacteria that causes strep throat (and associated bacterial tonsillitis) can result in the serious complications of rheumatic fever (which can lead to damage to the heart) and kidney disease. For this reason, it is important to seek medical advice and treatment if strep throat is suspected.

In some cases, tonsillitis can lead to a collection of pus next to one off the tonsils, called a peritonsillar abscess. A peritonsillar abscess can cause pain, difficulty swallowing, and swelling in the throat that can make breathing difficult. Get medical attention without delay at the first sign of breathing difficulties.

Tonsillitis can also cause blockage in the ear drum, leading to middle ear infections and/or glue ear.


Diagnosis is based on symptoms and examination of the throat. In addition to directly inspecting your throat and tonsils, your GP may take a throat swab if strep throat is suspected. The throat swab is sent to a laboratory for culture and identification of the bacteria causing the symptoms.

Your GP may suspect glandular fever in a teenager or younger child with tonsillitis, particularly if accompanied by the additional symptoms of severe lethargy and tiredness, swollen glands in the neck, armpits, and/or groin, and an enlarged spleen.


Treatment of viral tonsillitis primarily involves rest, recovery and symptom relief. It is also important to drink plenty of fluids and have regular meals (soft foods and smoothies are best).

If bacterial infection is confirmed by throat culture, antibiotics will be prescribed to prevent complications, particularly rheumatic fever and kidney disease. It is important to take the full course of antibiotics as prescribed to prevent the infection returning and to reduce the likelihood of developing rheumatic fever or kidney disease. Refer to our strep throat page for more information.

Antibiotics will not be prescribed for viral tonsillitis because antibiotics are not effective against viruses. Viral tonsillitis will usually get better without treatment. Pain relief and reduction of fever can be achieved with over-the-counter paracetamol and ibuprofen.

Gargling salt water (half teaspoon of salt to a cup of warm water) may provide some symptom relief as may sucking on hard sweets or throat lozenges containing ingredients that are cooling, anaesthetic, anti-septic, or anti-inflammatory.

Corticosteroids medicines may be prescribed to reduce inflammation and swelling, particularly when swallowing and breathing is difficult.


Improved care and the availability of effective antibiotics means that surgical removal of the tonsils (tonsillectomy) is less common today than it was previously. Tonsillectomy, however, may be recommended in people who have frequent episodes of tonsillitis, bacterial tonsillitis that does not respond to antibacterial medication, or are allergic to antibiotics.

Surgery does carry some risks, including bleeding during and after the operation in some people. Throat pain and difficulty eating is usual in the first few days after the operation. Full recovery typically takes two to three weeks.

Peritonsillar abscesses can be drained using a needle and syringe or by making an incision with a scalpel. Tonsillectomy is an option in those with a history of peritonsillar abscess.


Avoiding close contact with people who have tonsillitis is advisable to prevent passing on the infection. Children and other family members should be kept away from people with tonsillitis as much as possible.

Hygiene measures should also be used to prevent spread of infection. These include:

  • Regular and thorough washing and drying of hands
  • Using a tissue or inside of the elbow to cover coughs and sneezes
  • Frequent and thorough washing and drying of hands
  • Not sharing foods, liquids, eating utensils, or drinking vessels
  • Frequent cleaning of surfaces particularly in the kitchen and bathroom.

Support and further information

Additional information about tonsillitis and rheumatic fever can be obtained from Healthline, which is a free 24-hour telephone advice service provided by the Ministry of Health. Healthline is staffed by registered nurses who can advise and recommend appropriate care for callers with symptoms.


Freephone: 0800 611 116



NHS (2017). Tonsillitis (Web Page). Redditch: National Health Service (NHS) England. [12/08/20]
O’Toole, M.T. (Ed.) (2017). Rheumatic Fever. Mosby’s Dictionary of Medicine, Nursing & Health Professions (10th ed.). St Louis, MI: Elsevier.
O’Toole, M.T. (Ed.) (2017). Tonsillitis (Web Page). Mosby’s Dictionary of Medicine, Nursing & Health Professions (10th ed.). St Louis, MI: Elsevier.
Shah, U.K. (2020). Tonsillitis and peritonsillar abscess (Web Page). Medscape: Drugs & Diseases. New York, NY: WebMD LLC. [Accessed: 12/08/20]

Last reviewed: August 2020

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The purpose of the Southern Cross Medical Library is to provide information of a general nature to help you better understand certain medical conditions. Always seek specific medical advice for treatment appropriate to you. This information is not intended to relate specifically to insurance or healthcare services provided by Southern Cross.