How Enlarged Adenoids Can Affect Children’s Breathing, Sleep and Facial Development

Persistent snoring, mouth breathing, chronic runny nose and a blocked-nose sound can be signs of an enlarged adenoid, doctors say. In an article published June 26, 2026, Dr. Nadeem Habashi, a senior ENT physician at Rambam Medical Center, warned that when the problem is not diagnosed early, it can affect not only sleep but also facial and jaw development.

Habashi explained that the adenoid, also called the adenoids, is part of the immune system behind the nose and helps young children fight germs. Trouble starts when it grows too large and obstructs airflow. He said the clearest signs include snoring, mouth breathing, chronic mucus, drooling, nasal speech and recurring ear infections. Because the adenoid sits deep behind the nose, it cannot be seen in a routine throat exam, so diagnosis is often delayed. The critical age for detection is between 2 and 6, when the face and jaws are growing quickly.

According to Habashi, normal nasal breathing keeps the tongue on the palate and supports proper upper-jaw development. Chronic mouth breathing causes the tongue to drop, the upper jaw to remain narrow and high, and the lower jaw to grow downward and backward. Over time, children can develop the classic “adenoid face,” with a long face, open mouth, receding chin and tired appearance. If nasal breathing is restored early, many deformities can be prevented. After growth ends, complex orthodontic treatment and even surgery may be needed.

He said untreated children may later suffer from narrow palates, crowded teeth, a bad bite and sleep apnea, and some adults who come in at 30 or 40 with severe snoring or chronic fatigue discover they had breathed through their mouths since childhood. Poor sleep can also hurt concentration, memory and learning, and children may be mistakenly labeled as having ADHD. After treatment, many still need speech therapy to relearn proper breathing and swallowing, but he stressed that exercises alone cannot fix a physical blockage. Parents should seek an ENT evaluation if a child snores regularly, sleeps with an open mouth, struggles to breathe at night or has chronic nasal discharge.