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An inflammation of the tonsils caused by viruses or bacteria. Signs and symptoms include fever, enlargement of the tonsils, difficulty swallowing, and enlargement of the regional lymph nodes.

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(Source: NIH - National Cancer Institute)

About Tonsillitis

Sore throats can have a range of causes. Common cold viruses are usually to blame. In rarer cases, sore throats are caused by an infection of the tonsils (tonsillitis). This infection is often bacterial, or sometimes viral. But it isn't easy to tell what kind of germs are responsible for the infection. Children and teenagers are much more susceptible to tonsillitis than adults are.

Acute tonsillitis starts suddenly and usually goes away again within one to two weeks. But tonsillitis can return several times over the course of a year and may become chronic. In chronic tonsillitis, the bacteria become permanently settled in the tonsils, which are always slightly inflamed as a result. People who have chronic tonsillitis might keep getting acute infections with more severe symptoms too. Having chronic tonsillitis can be a real problem, and may also lead to complications in rare cases... Read more about Tonsillitis

What works? Research summarized

Evidence reviews

Surgical removal of the tonsils (tonsillectomy) for chronic or recurrent acute tonsillitis

This review compared the clinical effectiveness and safety of surgery (removal of the tonsils ‐ tonsillectomy, or adenotonsillectomy ‐ removal of the tonsils and adenoid tissues) against non‐surgical management in adults and children with frequent or chronic tonsillitis.

Antibiotics for preventing complications in children with measles

Measles is an infectious disease caused by a virus. There is an effective vaccine which can prevent measles, nevertheless 30 to 40 million people worldwide still develop measles annually. Each year measles causes more than half a million deaths and is responsible for an estimated 44% of the 1.7 million vaccine‐preventable deaths among children. Measles is associated with complications such as pneumonia, ear infections, throat infections, diarrhea and conjunctivitis.

The effect of short duration versus standard duration antibiotic therapy for streptococcal throat infection in children

Streptococcal (strep) throat infection is very common. A 10‐day course of penicillin is prescribed mainly to protect against the complication of acute rheumatic fever, which can occur approximately 20 days after streptococcal throat and cause damage to the heart valves. Cases of acute rheumatic fever have dropped dramatically in high‐income countries. Newer antibiotics taken for a shorter duration, may have a comparable effect to penicillin taken for 10 days.

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Summaries for consumers

Tonsillitis: Do antibiotics make sore throats go away quicker?

Antibiotics can shorten the length of throat infections by between half a day and one day on average. But they can have side effects, and using antibiotics too much increases the risk of bacteria becoming resistant to them.

Tonsillitis: Tonsil surgery in children

Most children only have tonsillitis every now and then. Although it is unpleasant, it usually gets better after a few days. But if tonsillitis keeps coming back over several years, the option of surgically removing the tonsils is often considered. Acute bacterial infections of the tonsils cause symptoms such as a sore throat, difficulty swallowing, fever and tiredness. Breathing problems and snoring can disrupt sleep. But sore throats might also be caused by a viral throat infection. Even doctors often find it difficult to distinguish between these two types of infections. Tonsillitis that keeps coming back within short spaces of time can be very distressful. Children and teenagers are much more susceptible to tonsillitis than adults are. Some children get tonsillitis four to eight times a year, with each episode lasting one to two weeks. They keep having to miss school as a result – and their parents often have to stay at home to take care of them.Location of the tonsils Sometimes tonsils become permanently inflamed, causing things like breathing problems. Painkillers and antibiotics might not be effective enough, or people might not want to use too much medication. Complications such as the collection of pus beside a tonsil (known as quinsy or a peritonsillar abscess) are a further reason why surgery might be considered. When considering surgery, it is worth weighing the pros and cons: On the one hand there is the hope that having tonsils out will reduce the number of infections, or even stop them altogether. On the other hand the surgery is associated with risks, and you cannot be sure that it will actually help.

Tonsillitis: Overview

Symptoms of acute tonsillitis include sore throat, difficulty swallowing, fever and fatigue. More frequent tonsil infections can be a real problem, and may also lead to complications in rare cases.

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Terms to know

Describes something that happens suddenly and for a short time. Opposite of chronic, or long lasting.
Surgical removal of the pharyngeal tonsils (adenoids).
Surgical removal of the tonsils and adenoids.
A large group of single-cell microorganisms. Some cause infections and disease in animals and humans. The singular of bacteria is bacterium.
Refers to disorders that last a long time, often years. Chronic is the opposite of acute, or brief.
Common Cold
Caused by viruses. Signs and symptoms include fever, coughing, sneezing, and sore throat.
Lingual Tonsils
Two lingual tonsils are in the mouth, one on each side of the tongue. They are composed of lymphatic tissue that functions to assist the immune system in the production of antibodies.
Lymph Nodes
A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels. Also called lymph gland.
Palatine Tonsils
The two tonsils that can be seen on the left and right sides at the back of the throat.
Pharyngeal Tonsils (Adenoids)
Small pad of infection-fighting tissue located near the eustachian tube.
Inflammation of the throat most often caused by viral and bacterial infections. Other causes include allergens, chemical substances, and trauma.
Surgical removal of the tonsils.
Two small masses of lymphoid tissue on either side of the throat.
In medicine, a very simple microorganism that infects cells and may cause disease. Because viruses can multiply only inside infected cells, they are not considered to be alive.

More about Tonsillitis

Photo of a child

See Also: Strep Throat, Sore Throat

Other terms to know: See all 14
Acute, Adenoidectomy, Adenotonsillectomy

Related articles:
How the Tonsils Work

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