Olaya Gutierrez is a Gastroenterologist in Washington, Washington, D.c.. Dr. Gutierrez is rated as an Advanced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). Her top areas of expertise are Achalasia, Gastroesophageal Reflux Disease (GERD), Choledocholithiasis, Endoscopy, and Lithotripsy.

Dr. Brett Parker is a general surgeon and fellowship-trained minimally invasive foregut and bariatric surgeon. He is an Assistant Professor of Surgery at Johns Hopkins and also the Program Director for the Johns Hopkins Advanced GI and Minimally Invasive Surgery Fellowship Program. Dr. Parker is an expert in minimally invasive surgical techniques including advanced laparoscopy and robotic surgery, as well as therapeutic flexible endoscopy. He is interested in promoting the evolving indications for surgical repair of hiatal hernias, as well as adjunct procedures surgeons can use to reduce recurrence rates. He offers a wide range of interventions for GERD, including innovative endoscopic therapies, and promotes early surgical referral to discuss and tailor therapy to individual patient circumstances. Dr. Parker also has a robust abdominal wall reconstruction and weight loss surgery practice. He is widely published on the surgical outcomes of foregut surgery, emerging technologies, and innovation, as well as surgical simulation and skills transfer. Dr. Parker has consistently been selected as a Washingtonian Magazine Top Doctor in 2023, 2024, and 2025. As a member of the Johns Hopkins Division of Minimally Invasive Surgery in the Greater Washington Area, Dr. Parker is dedicated to the best, individualized, patient outcomes. Learn more about Dr. Parker and his partners within the Johns Hopkins Division of Minimally Invasive Surgery, the Johns Hopkins Heartburn Center and the Johns Hopkins Motility and Neurogastroenterology Center. Dr. Parker is rated as an Advanced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Hiatal Hernia, Hernia, Congenital Diaphragmatic Hernia, Endoscopy, and Gallbladder Removal.

Nikiya Asamoah-Clark is a Gastroenterologist in Washington, Washington, D.c.. Dr. Asamoah-Clark is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). Her top areas of expertise are Ulcerative Colitis, Crohn's Disease, Familial Adenomatous Polyposis, Endoscopy, and Gastrectomy.

Christopher Hayes is a Pediatrics specialist and a Gastroenterologist in Washington, Washington, D.c.. Dr. Hayes is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Fecal Impaction, Delayed Growth, Encopresis, and Familial Short Stature (FSS). Dr. Hayes is currently accepting new patients.

Robert Musselman is a Gastroenterologist in Washington, Washington, D.c.. Dr. Musselman is rated as a Distinguished provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Gastroesophageal Reflux Disease (GERD), Gastric Dysmotility, Hemorrhoids, and Diverticular Disease.

Dr. Dominique Howard is a gastroenterologist affiliated with Sibley Memorial Hospital and George Washington University Hospital. She practices out of Capital Digestive Care’s Metropolitan Gastroenterology Group in Washington, D.C. and Chevy Chase, Md. Dr. Howard has an expertise in inflammatory bowel disease, irritable bowel syndrome, gastroesophageal reflux disease, esophageal pH testing, capsule endoscopy, colorectal cancer screening and diseases of the pancreas and gallbladder. Dr. Howard earned her undergraduate degree from Georgetown University and her medical degree from George Washington University School of Medicine. She completed a residency in internal medicine at George Washington University Hospital, followed by a fellowship in gastroenterology. Dr. Howard is a member of the American Gastroenterological Association, the American Society of Gastrointestinal Endoscopy, the Crohn’s and Colitis Foundation and the William Earl Clark Society. Dr. Howard is rated as an Advanced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). Her top areas of expertise are Gastroesophageal Reflux Disease (GERD), Trichohepatoenteric Syndrome, Diarrhea, and Attenuated Familial Adenomatous Polyposis.

Julio Salcedo is a Gastroenterologist in Washington, Washington, D.c.. Dr. Salcedo is rated as an Advanced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Hemorrhoids, Gastroesophageal Reflux Disease (GERD), Gastrointestinal Bleeding, Endoscopy, and Gastrectomy.

Ramsey Daher is a Gastroenterologist in Washington, Washington, D.c.. Dr. Daher is rated as an Advanced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Heartburn, Gastric Dysmotility, Familial Adenomatous Polyposis, Gastrectomy, and Colonoscopy.

Antoinette Saddler, M.D., is a fellowship-trained gastroenterologist specializing in general gastroenterology and management of patients with mild to severe malnutrition. She has experience in treating complex gastrointestinal disorders including short bowel syndrome, celiac disease, inflammatory bowel disease, irritable bowel syndrome, gastrointestinal malignancies, gastrointestinal tract dysmotility and high-output ostomies, as well as the malnutrition associated with these conditions. Dr. Saddler has held positions at the University of Kentucky, MedStar Washington Hospital Center, the University of Virginia School of Medicine, and the George Washington University School of Medicine and Health Sciences. She has also been a private practice gastroenterologist. Her professional activities include regional and national lectures on the management of gastrointestinal disorders associated with malnutrition. She previously served as the director of medical nutrition at the University of Virginia Digestive Health Center, where patients with complex gastrointestinal and nutritional disorders receive care. Dr. Saddler obtained her medical degree at the Case Western Reserve University School of Medicine. She completed her residency training in internal medicine at New York-Presbyterian/Weill Cornell Medical Center followed by fellowship training in gastroenterology at Memorial Sloan Kettering Cancer Center. She pursued additional fellowship training there in clinical nutrition. Dr. Saddler is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). Her top areas of expertise are Gastroparesis, Chronic Erosive Gastritis, Familial Adenomatous Polyposis, Endoscopy, and Gastrectomy.

Christopher Duke, MD is a second-generation physician and native Washingtonian. His parents practiced medicine in Washington for four decades. Chris has practiced internal medicine here for 30 years. He attended George Washington University for his undergraduate and medical degrees. He completed Internal Medicine training at Penn State University. Chris practices evidence-based medicine while emphasizing empathy for his patients and their families. He personally knows and refers patients to the many outstanding specialists in Washington. He is excited to team with his patients to optimize their health and enjoyment of life. He has taught medical students at George Washington as an associate professor of medicine. He has been recognized by Washingtonian Magazine as a “Top Doctor” including in 2022. Outside of work, he enjoys traveling with wife Lilian and children Jacqueline and James. He loves attending Notre Dame football games and spoiling his pugs- Mini and Rockne! LinkedIn https://www.linkedin.com/in/christopher-duke-md-1126314. Dr. Duke is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Rabson-Mendenhall Syndrome, Vitamin B12 Deficiency, Subacute Combined Degeneration, and Cellulitis.

Dr. Drew Jung is an assistant professor of surgery in the Johns Hopkins Department of Surgery. He is an expert in minimally invasive surgery whose clinical focus is in laparoscopic and robotic surgeries. He has specialties in open and laparoscopic hernias, bariatrics, foregut, and quality improvement as it pertains to quality of care. Dr. Jung is focused on being able to get patients back on their feet sooner and have the potential to get back to work sooner than before. He is open to accepting all new patients to provide his expertise. Videos Dr. Andrew Jung M.D Bio Video. Dr. Jung is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Hernia, Hemolytic Transfusion Reaction, Low Blood Pressure, Sleeve Gastrectomy, and Gastrectomy.

Dr. Vera L. Sheen is a Johns Hopkins Community Physician practicing out of Sibley Primary Care located in Sibley Memorial Hospital’s Medical Building in Washington, D.C. She is affiliated with Georgetown University Hospital as well. Dr. Sheen has an expertise in internal medicine. Dr. Sheen earned her medical degree from University of Kentucky College of Medicine. She completed a residency in internal medicine at Barnes-Jewish Hospital. Dr. Sheen is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). Her top areas of expertise are Vitamin D Deficiency, High Cholesterol, Vitamin B12 Deficiency Anemia, and Folate Deficiency.

Dr. Andrew N. Umhau is an internist affiliated with Sibley Memorial Hospital and Georgetown University Hospital. He practices out of Foxhall Internists in Washington, D.C. Dr. Umhau has an expertise in general internal medicine, with clinical interests in adolescent and young adult medicine, medical problems of pregnancy and cross-cultural issues. Dr. Umhau earned his undergraduate degree from Davidson College and his medical degree from Duke University. He completed a residency in internal medicine at Georgetown University, where he became chief resident. Dr. Umhau was named a Super Doctor by the Washington Post and has been named one of the Best Doctors in America. Castle Connolly named him a Top Doctor in the Washington, D.C. and Washington-Baltimore areas in 2012. Dr. Umhau also earned the 2009 Laureate Award by the American College of Physicians, Washington, D.C. chapter. Dr. Umhau is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are High Cholesterol, Recurrent Peripheral Facial Palsy, Facial Paralysis, and Bell's Palsy.

Dr. James G. Vap is an otolaryngologist affiliated with Sibley Memorial Hospital and Georgetown University Hospital. He practices out of ENT Medical Group of Washington, located in Washington, D.C. and McLean, Va. Dr. Vap has an expertise in otology, otolaryngic allergy, rhinology and sinus disease. Dr. Vap earned his medical degree at the University of California at Davis School of Medicine. He completed a residency in otolaryngology at Huntington Memorial Hospital and an otology fellowship at the University of Southern California School of Medicine. Dr. Vap previously served as a medical staff specialist at the National Naval Medical Center. Dr. Vap is a fellow of the American Academy of Otolaryngology and the American College of Surgeons. He has served as a consultant to the National Institutes of Health, the Walter Reed Army Medical Center and the Medical Advisory Board of the Treatment and Learning Center. Dr. Vap is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Common Cold, Meniere Disease, Tinnitus, and Empyema.

William Condrell is a primary care provider, practicing in Family Medicine in Washington, Washington, D.c.. Dr. Condrell is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Attention Deficit Hyperactivity Disorder (ADHD), Erectile Dysfunction (ED), Persistent Genital Arousal Disorder, and Insomnia.

Dr. Louis Y. Korman is a gastroenterologist affiliated with Sibley Memorial Hospital, Washington Hospital Center and George Washington University Hospital. He is also an instructor of the internal medicine and gastroenterology training program at the Veterans Administration Hospital/Georgetown University Residency and Fellowship program. He practices out of Capital Digestive Care’s Metropolitan Gastroenterology Group, located in Washington, D.C. and Bethesda, Md. Dr. Korman earned his medical degree at SUNY Upstate Medical University. He completed a residency in internal medicine at SUNY Upstate Medical Center, as well as a fellowship in gastroenterology. Dr. Korman is a fellow of the American College of Gastroenterology and a member of the American Society of Gastrointestinal Endoscopy, the American Association for the Advancement of Science, the American College of Physicians, the American Medical Association, as well as other professional organizations. He was previously a chairman of the Crohn’s and Colitis Foundation Medical Advisory Board and a chairman of the Home Health Care Committee of the Jewish Social Services Agency. Dr. Korman has been repeatedly named a Top MD in Washingtonian Magazine and Consumers’ Checkbook Magazine, as well as a 2014 Regional Top Doctor by Castle Connolly. He also earned the American Gastroenterological Society’s Distinguished Clinician of the Year Award in 2015. Dr. Korman has contributed to numerous publications and presentations on gastroenterology topics. Dr. Korman is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Autoimmune Hepatitis, Stomach Cancer, Ulcerative Colitis, Colonoscopy, and Endoscopy.

Nicole Singh is a primary care provider, practicing in Family Medicine in Washington, Washington, D.c.. Dr. Singh is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). Her top areas of expertise are Macroamylasemia, Juvenile Primary Osteoporosis, High Cholesterol, and Gastroesophageal Reflux Disease (GERD).

Dr. Lawrence E. Klein is an internist affiliated with Sibley Memorial Hospital; Johns Hopkins Hospital, where he holds a part-time faculty appointment; and Georgetown University Hospital, where he also holds a faculty appointment. He practices out of Foxhall Internists in Washington, D.C. Dr. Klein completed a joint M.D.-Ph.D. program at Johns Hopkins University School of Medicine, where he was elected into the AOA Medical Honor Society. He completed a residency in internal medicine at Strong Memorial Hospital of the University of Rochester, followed by a fellowship in internal medicine at Johns Hopkins Hospital. Dr. Klein was one of the country’s first Henry J. Kaiser Foundation fellows in internal medicine. He went on to serve as a full-time Johns Hopkins medical faculty member. Dr. Klein previously served as the president of the D.C. Society of Internal Medicine and the governor of the D.C. Chapter of the American College of Physicians. Dr. Klein has been repeatedly named a Top Doctor in Washingtonian magazine and Consumers’ Checkbook magazine, as well as named a Super Doctor in the Washington Post magazine and one of the Best Doctors in America. He was awarded the American College of Physicians John H. Maher Laureate Award in 2001 and inducted as a Master of the American College of Physicians in 2009. Dr. Klein has contributed to numerous publications and presentations, abstracts and posters, and lectures on various topics. Dr. Klein is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Chronic Lymphocytic Leukemia (CLL), Chronic B-Cell Leukemia (CBCL), Richter Syndrome, and Familial Hypertriglyceridemia.

Michael Grady is a primary care provider, practicing in Family Medicine in Washington, Washington, D.c.. Dr. Grady is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are Dementia, Chronic Kidney Disease, Hypertension, and Familial Hypertension.

Dr. John A. Dooley is an internist affiliated with Sibley Memorial Hospital and Georgetown University Hospital. He practices out of Foxhall Internists in Washington, D.C. Dr. Dooley earned his undergraduate degree from Harvard University and his medical degree from Columbia University College of Physicians and Surgeons, where he received the Robert Loeb Award for Excellence in Clinical Medicine. He completed a residency in internal medicine at Johns Hopkins University School of Medicine. Dr. Dooley previously practiced general internal medicine at the Veterans Affairs Medical Center. Dr. Dooley has been named a Top Doctor by Consumers’ Checkbook Magazine. Dr. Dooley is rated as an Experienced provider by MediFind in the treatment of Gastroesophageal Reflux Disease (GERD). His top areas of expertise are High Cholesterol, Pyomyositis, Familial Hypertension, and Hypertension.