Tonsillar hypertrophy is a persistent enlargement of the tonsils. Tonsil enlargement does not usually cause symptoms, but if it is severe it can block the throat and affect the patient’s breathing. Infectious causes of tonsillar hypertrophy can result in symptoms such as sore throat and fever. The tonsils are two glands located at the back of the throat on either side. They are part of the immune system and help fight off germs. When hypertrophy occurs, it may cause varying degrees of narrowing of the passage of air into the airways, causing breathlessness or labored breathing. As the nose becomes difficult to breathe, it then becomes open-mouth breathing, making noisy breathing and increased snoring. In some severe cases, obstructive sleep apnea may occur, resulting in restless sleep. Foul breath may occur in the mouth. Tonsillar hypertrophy is often seen in children. Childhood is a period of vigorous tonsillar proliferation, and some children are born with only large tonsils, which may also be related to genetic factors or may be due to air pollution. In some children and adults, enlarged tonsils can also be a sign of bacterial and viral infections, and can also present with symptoms of laryngitis, chills, and also some symptoms of infection such as fever and fatigue. Enlarged tonsils can interfere with sleep, and in more severe cases, surgical treatment can eliminate enlarged tonsils.