Diseases & Conditions


Tonsils and Adenoids (Enlarged)

Locating the Tonsils and Adenoids

The tonsils are two areas of lymphoid tissue located on either side of the throat. The adenoids, also lymphoid tissue, are located higher and further back, behind the palate, where the nasal passages connect with the throat. The adenoids are not visible through the mouth.

Tonsils and adenoids are collections of lymphoid tissue that help the body fight infection. The tonsils are located on both sides of the back of the throat. The adenoids are located higher and further back, where the nasal passages connect with the throat, and are not visible through the mouth. However, tonsils and adenoids can become enlarged—for example, when they become infected with bacteria that cause pharyngitis. When this happens, the tonsils become more prominent and the adenoids may block the nose. Usually, the tonsils and adenoids return to normal size once the infection is over. Sometimes they remain enlarged, particularly in children who have had frequent or chronic infections. Although extremely rare, cancer sometimes causes enlarged tonsils or adenoids in children.


Most enlarged tonsils and adenoids cause no symptoms; some degree of tonsillar enlargement is even considered normal in preschool and adolescent children. However, children with enlarged tonsils or adenoids can experience sore throat and discomfort or pain with swallowing. Enlarged adenoids can give the voice a "pinched nose" quality and lead to changes in the shape of the child's palate and the position of the teeth.

Enlarged tonsils and adenoids are considered a problem when they cause more serious effects. They can cause chronic ear infections and hearing loss due to obstruction of the eustachian tube and fluid accumulation in the middle ear. They can also cause recurring sinus infections and nosebleeds. Some children have obstructive sleep apnea (see Sleep Apnea ), with snoring and brief periods without breathing; this can cause low oxygen levels in the blood, frequent waking, and daytime sleepiness. Rarely, obstructive sleep apnea caused by enlarged tonsils and adenoids can lead to serious complications, such as high blood pressure in the lungs (pulmonary hypertension) and changes in the heart that result from pulmonary hypertension (cor pulmonale—see Pulmonary Hypertension:Pulmonary Hypertension ).

Children with enlarged tonsils can also lose or fail to gain weight, either because of pain and difficulty eating or because of the constant physical effort it takes for them to breathe.

Diagnosis and Treatment

Doctors do not rely on the size of the tonsils alone to make the diagnosis. Very large tonsils may be normal, and chronically infected tonsils may be normal-sized. Instead, doctors look for redness of the tonsils, enlargement of lymph nodes at the jaw and in the neck, and the effect of the tonsils on breathing. The diagnosis of obstructive sleep apnea is suspected when parents report frequent periods without breathing. Doctors may also recommend a polysomnogram, in which oxygen in the blood is measured and the child is observed while sleeping.

Doctors may give antibiotics if they think a bacterial infection may be the cause of the enlarged tonsils. If antibiotics are not effective or if doctors think antibiotics will not be useful, they may recommend the surgical removal of the tonsils and adenoids (tonsillectomy and adenoidectomy).

Tonsillectomy and adenoidectomy used to be very common operations performed on children in the United States, but they are much less common now that doctors are more aware of which children will benefit from the operation. Children who benefit from surgery include those with obstructive sleep apnea and those whose talking and breathing are extremely uncomfortable. Doctors may also recommend surgery if they think cancer might be a cause of the enlargement, or if the child has had multiple throat or ear infections (defined by some as seven or more infections in 1 year, five or more infections a year over 2 years, or three or more a year over 3 years). A doctor may recommend adenoidectomy alone for ear infections, recurring nasal congestion, or sinus infections.

Tonsillectomy and adenoidectomy have not been shown to decrease the frequency or severity of colds, cough, and other symptoms. These procedures should be performed at least 3 weeks after any infection has cleared.

Tonsillectomy and adenoidectomy are usually performed on an outpatient basis. The surgical complication rate is low, but postoperative pain and difficulty swallowing may last up to a week. Bleeding is a less common complication but may occur anytime from the first day of surgery to the tenth day after surgery.

Last full review/revision February 2003

Source: The Merck Manual Home Edition