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URL of this page: //medlineplus.gov/ency/presentations/100143.htm

Achalasia - series—Normal anatomy

Achalasia - series

Overview

The esophagus carries food from the mouth to the stomach. The lower esophageal sphincter is a muscular ring at the junction of the esophagus and the stomach. The lower esophageal sphincter relaxes when food from the esophagus enters the stomach.

Review Date 10/20/2025

Updated by: Todd Eisner, MD, Private practice specializing in Gastroenterology in Boca Raton and Delray Beach, Florida at Gastroenterology Consultants of Boca Raton. Affiliate Assistant Professor, Florida Atlantic University School of Medicine. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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