Adenoids are masses of tissue located high on the posterior wall of the pharynx. They are made up of lymphatic tissue, which trap and destroy pathogens in the air that enter the nasopharynx.
Review Date: 8/5/2015
Reviewed By: Sumana Jothi MD, specialist in laryngology, Clinical Instructor UCSF Otolaryngology, NCHCS VA, SFVA, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team