What is tonsillitis?

Tonsillitis occurs when the tonsils become infected and inflamed. Tonsils are the two small lumps of soft tissue — one on either side — at the back of the throat. You can see your tonsils in a mirror by opening your mouth and sticking out your tongue.

As part of your immune system, tonsils trap some of the germs that make you sick. When tonsils become infected, they get swollen and sore, and swallowing may hurt. Tonsillitis is also called tonsillopharyngitis, but most people call it a sore throat.

How common is tonsillitis?

Tonsillitis is very common. Most people have tonsillitis at least once in their lifetime.

Who is affected by tonsillitis?

Tonsillitis is most common in children, but it can affect people of all ages. Tonsillitis rarely occurs in children under the age of 3.

What are the symptoms of tonsillitis?

Symptoms of tonsillitis usually come on suddenly. Common symptoms include:

  • Sore or scratchy throat
  • Pain or difficulty swallowing
  • Red, swollen tonsils and throat
  • Whitish spots on the tonsils, or a white, yellow or gray coating on the tonsils
  • Fever above 100.4 degrees
  • Swollen lymph nodes (glands on the sides of your neck below your ears)
  • Stomachache or vomiting (more frequently in younger children)

What causes tonsillitis?

A virus or bacteria causes tonsillitis. The two types of tonsillitis are:

  • Viral tonsillitis: Most cases (up to 70 percent) of tonsillitis are caused by a virus such as cold or flu (influenza).
  • Bacterial tonsillitis (strep throat): Other cases of tonsillitis are caused by group A Streptococcus bacteria. Bacterial tonsillitis is commonly called strep throat.

How do people get tonsillitis?

The viruses and bacteria that cause tonsillitis are highly contagious. They are passed along by:

  • Kissing or sharing utensils, food or drink
  • Coming into close contact with someone who is sick
  • Touching a contaminated surface and then touching your nose or mouth
  • Inhaling tiny particles that become airborne when a sick person sneezes or coughs

Last reviewed by a Cleveland Clinic medical professional on 06/11/2019.


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