Tonsillitis: Infection of the Tonsils

Tonsillitis is inflammation, from infection, of the tonsils (the infection-fighting lymph tissue located on either side of the back of the mouth). It is most common in children between the ages of five and 15—although it can occur at any age—and is characterized by a severe sore throat.

Once considered a nuisance and frequently removed surgically, the tonsils are now known to serve a role, though a somewhat limited one, in immune surveillance. They are the respiratory system’s first line of defense, trapping and neutralizing infectious agents before they can penetrate the bronchial passages.

Children’s tonsils are normally large; they reach their maximum size at around age six or seven and then start to shrink. Because of their continuous exposure to infectious agents, the tonsils sometimes become overwhelmed by infection, resulting in tonsillitis.

Although tonsillitis usually goes away on its own within a week, it still warrants a physician’s attention to identify the infectious agent. Bacterial infections, particularly strep throat, require prescription medication, because an immunologic reaction to products formed by group A streptococci causes glomerulonephritis or rheumatic fever.

A serious infection can also lead to peritonsillar abscess, an accumulation of pus in the tissues around the tonsils. Chronic, recurrent tonsillitis may require surgical removal of the tonsils (tonsillectomy).

What Causes Tonsillitis?

  • Viruses are the most common cause; bacteria account for some 40 percent of cases. Germs that cause tonsillitis are usually spread via hand-to-hand and hand-to-mouth contact.

Symptoms of Tonsillitis

  • Sore, red, raw throat; swallowing difficulty
  • Gray or white patches on the tonsils or the soft palate
  • Fever, chill
  • Headache
  • Swollen lymph nodes in the jaw and neck
  • Ear pain
  • Nausea, vomiting and abdominal pain (common in children)
  • Loss of voice (called laryngitis)

Tonsillitis Prevention

  • Normal infection-fighting measures can help reduce the incidence of tonsillitis. Chief among these is frequent hand washing, especially in winter when germs are spread more easily owing to close indoor contact. Young children should be taught to cover their mouths when they sneeze or cough.
  • Ensure that you practice good hand-washing habits.
  • Prompt treatment will limit transmission to others.
  • Avoid sharing of eating utensils or drinking glasses.

Diagnosis of Tonsillitis

  • Patient history and physical examination are necessary. Streptococcal tonsillitis cannot be distinguished from viral causes by its clinical features.
  • Throat swabs are cultured to identify the underlying infectious agent and so determine the proper treatment.
  • More rapid tests are available to quickly identify group A streptococci.

How to Treat Tonsillitis

  • Antibiotics are prescribed for streptococcal or other bacterial infections and must usually be taken for at least 10 days.
  • Acetaminophen or other nonprescription pain-relieving and fever-reducing medications are recommended to relieve discomfort. Do not give aspirin to those under 16 years of age, however, as it may trigger a potentially life-threatening disorder.
  • Gargling with a salt-water solution several times a day may relieve sore throat.
  • Surgical drainage may be required if an abscess develops.
  • If tonsillitis becomes chronic, or tonsil size interferes with breathing or swallowing, tonsillectomy may be recommended. This procedure is often done on an outpatient basis.

When to Call a Doctor

  • Call a doctor if a sore throat does not go away within 48 hours, especially if accompanied by fever.
  • Call a doctor if a sore throat worsens, especially on one side, despite antibiotic therapy.


Johns Hopkins Symptoms and Remedies: The Complete Home Medical Reference

Simeon Margolis, M.D., Ph.D., Medical Editor

Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50

Updated by Remedy Health Media

Publication Review By: the Editorial Staff at

Published: 25 Aug 2011

Last Modified: 03 Mar 2015