Adenoiditis is the inflammation of the adenoids, which are small glands located at the back of the throat. These glands help fight infections, but when they become swollen, they can cause symptoms like a sore throat, difficulty breathing, and nasal congestion. Adenoiditis is often caused by viral or bacterial infections. This condition is more common in children, as their adenoids are larger and more active during early development. Treatment may include rest, fluids, and over-the-counter medications to relieve symptoms. In severe cases, a doctor may recommend surgery to remove the adenoids.