This occurs if the tonsils are so large that they block breathing. Enlarged tonsils can also cause obstructive sleep apnea and are removed in those cases. Tonsillectomy is also recommended in individuals with just one enlarged tonsil in order to biopsy the tissue. A peritonsillar abscess must be drained in some way. Relatively small or contained abscesses can be drained by aspirating the pus with a needle, using a local anesthetic.
More severe infections require a general anesthetic and drainage in the operating room.
A tonsillectomy is a surgical procedure done under a general anesthetic. The tonsil is surrounded by a capsule of tissue. The surgeon uses special instruments to remove the tonsil by dissecting between this capsule and the adjacent throat tissue. For otherwise healthy individuals, tonsillectomy can in most cases the be done on an out-patient basis. The site where the tonsils were taken out heals on its own.