A peritonsillar abscess is a pocket of pus that forms in the space around the tonsils.

What is going on in the body?

A peritonsillar abscess forms when tonsillitis spreads beyond the tonsils. The infection travels into the space between the tonsil and the underlying muscle. This infection then forms a gradually enlarging abscess, or pocket of pus.

What are the causes and risks of the infection?

Most episodes of peritonsillar abscess follow tonsillitis, or an infection of the tonsils. These infections are usually caused by bacterial organisms called group A streptococci. Obstruction of certain glands around the mouth may also cause a peritonsillar abscess.

A person who has had peritonsillar abscess or chronic tonsillitis in the past is at a higher risk for another in the future. Peritonsillar abscesses are rare in children. They are more common in adolescents and adults.