What is tonsillitis?

Tonsillitis means that your tonsils are inflamed. Your tonsils are large, fleshy glands at the back of your throat. These glands make antibodies that help fight infection.

What causes tonsillitis?

Both bacteria and viruses can cause tonsillitis. Here are some of them:

  • Streptococcus, or strep, bacteria. These germs are the most common cause.
  • Adenoviruses
  • Epstein-Barr virus, which causes infectious mononucleosis
  • Herpes simplex virus
  • Cytomegalovirus
  • Measles virus 

These germs are often easily passed
from one person to another (contagious).

What are the symptoms of tonsillitis?

Each person may have slightly different symptoms. These are the most common symptoms of tonsillitis:

  • Swollen, red tonsils. They may look yellow, gray, or white.
  • Blisters or painful sores on the throat
  • Sore throat that happens suddenly
  • Pain when swallowing or difficult to swallow
  • Snoring
  • Foul breath
  • Headache
  • Loss of appetite
  • Tiredness
  • Chills
  • Fever
  • Swollen and tender lymph nodes in the neck or jaw area

You may not have any symptoms but still have the strep bacteria. You can pass these bacteria on to another person.

A complication of tonsillitis is an area around the tonsils filled with bacteria. This is called a peritonsillar abscess. You may have these symptoms:

  • Severe throat pain
  • Muffled voice 
  • Drooling
  • Trouble opening mouth

The symptoms of tonsillitis may look like other conditions or health problems. Always see your healthcare provider for a diagnosis.

How is tonsillitis diagnosed?

Your healthcare provider will ask about your health history and do a physical exam. Your provider may do a strep test if he or she thinks the infection is caused by strep bacteria. Or your provider may do this test to rule out strep as the cause. To do this test, your provider will take a swab of your tonsils.