Swollen adenoids can be caused by infection or inflammation. In some cases, they are natural, a result of entirely normal variations in the size and shape of the adenoids. When swollen adenoids are identified, a doctor will determine whether they are causing problems for the patient and make treatment recommendations on that basis. Sometimes, the recommended treatment is no treatment at all, allowing the problem to resolve on its own.
The adenoids are masses of glandular tissue found in the back of the throat. They act to trap viruses and bacteria and are part of the immune system. They usually continue to grow until people reach the age of five or six, and remain the same size throughout a person's life. The adenoids and tonsils, similar tissue located in the mouth, are closely linked, and often when something is wrong with the tonsils, it can also be seen in the adenoids, and vice versa.
One reason for swollen adenoids is because the tissue is doing its job. If bacteria and viruses reach the throat and are caught by the adenoids, they will swell. The body may be able to fight off the infection on its own, or it may need some help with antibiotics or antiviral drugs to kill the organisms causing the infection. Over time, chronic inflammation of the adenoids as a result of repeat infections can also contribute to swelling.
Allergies can also lead to swollen adenoids. In people with allergies, the immune system incorrectly identifies ordinary substances are harmful and exposure to these substances triggers an immune reaction. When allergens reach the adenoids, the immune system triggers inflammation in response and the adenoids swell. Chronic allergies can create persistently swollen adenoids.
In some people, the adenoids are simply large. This is entirely natural and is not a response to environmental conditions or other factors. If a patient presents with large adenoids and no signs of infection or inflammation, a doctor may determine the tissue is simply larger in that individual.
Swollen adenoids can obstruct breathing, lead to ear infections, and cause other problems. If the swelling cannot be treated, a doctor may recommend an adenoidectomy to remove the tissue. Historically, tonsillectomies and adenoidectomies were widely recommended by medical practitioners. Today, doctors are more hesitant because this tissue appears to play an important role in immune function. A doctor will try options like antibiotics first to see if removal can be avoided.