The tonsils are part of the lymphatic system and work with the immune system. When the tonsils become infected or overwhelmed by the very microbes that they help to fight, they can become enlarged. The following are common causes of enlarged tonsils:
- Strep throat
- The common cold virus, including cytomegliovirus (CMV) and herpes simplex virus
- Mononucleosis (sometimes just called mono)
- Measles
Strep throat, caused by the streptococcus bacteria, can have serious complications if left untreated. For this reason, you should see a doctor whenever you have enlarged tonsils to evaluate you for strep throat.
Treatment of Enlarged Tonsils
Enlarged tonsils that are caused by a bacteria, such as streptococcus, can be treated with antibiotics. There is no medication that can cure enlarged tonsils caused by viruses, though it may be possible to reduce the swelling with steroids in severe cases. Rarely, the tonsils become so enlarged that they interfere with breathing or sleeping and have to be surgically removed.
Sources:
American Academy of Otolaryngology - Head and Neck Surgery. Fact Sheet: Tonsillitis. Accessed: January 22, 2011 from http://www.entnet.org/HealthInformation/tonsillitis.cfm
Medline Plus. Tonsillitis. Accessed: January 22, 2011 from http://www.nlm.nih.gov/medlineplus/ency/article/001043.htm

