Dr. Mark Christopher Mattar, MD

Dr. Mark Christopher Mattar, MD

Dr. Mark Christopher Mattar, MD

Languages: English, Arabic, Spanish
Phone: 202-444-8541
Fax: 877-303-1462

Contact this Provider:

  • Gastroenterology
Conditions I Treat
  • anal fissure
  • anal fistula
  • bright red blood per rectum
  • celiac disease
  • clostridium difficile
  • Show All
Procedures I Perform
  • biologic therapy for gastrointestinal diseases
  • colon polypectomy
  • colonoscopy
  • early detection of cancer
  • endoscopic mucosal resection of large colon polyps
  • Show All
About the Provider

Dr. Mattar is the Quality Improvement Officer for the Division of Gastroenterology.

As the director of the IBD Center he has expertise in diagnosing and treating inflammatory bowel diseases (IBD)Crohn's disease, colitis, and celiac disease. Dr. Mattar has a particular interest in IBD therapeutics and IBD and colorectal cancer prevention. He is active in clinical research and medical education for trainees, the community, and patients.
Dr. Mattar sees patients in his gastroenterology practice at MedStar Georgetown University Hospital. He embraces a team approach to patient care within the IBD Center at MedStar Georgetown as part of a multidisciplinary treatment team that includes dietitians and other key providers. He is also active in clinical trials for IBD and performs fecal microbiota transplantation for recurrent and refractory C. difficile infection.

Dr. Mattar teaches at MedStar Georgetown University Hospital as Associate Professor of Medicine, and is the director of the Fellowship Training Program in Gastroenterology. He is also an active member of the mission committee of the Crohn's and Colitis Foundation, D.C. Metro chapter; the ACG Training Committee and the Patient Education National Scientific Advisory Committee for the Crohn’s and Colitis Foundation. In 2014, Dr. Mattar was recognized by the American Gastroenterological Association's Bridges to Excellence Program for his commitment to providing comprehensive quality care for patients with IBD.

Dr. Mattar enjoys family time with his wife and son, including fishing in local ponds and creeks. He especially enjoys exploring the Washington museums and playgrounds with his young son. He also enjoys checking out the local cafes and creating his own latte art. 

Patients and practitioners can connect with Dr. Mattar on Twitter (@gastrodocmattar) and follow his tweets on new developments in gastroenterology.

The mission of the training program he directs states, "To create an environment where compassionate medical trainees can learn to provide exceptional quality care to the patients we serve." He prides himself in treated his patients as he would his own family.


  • Fellowship Program: MedStar Georgetown University Hospital (2010)
  • Residency Program: Olive View - UCLA Medical Center (2007)
  • Medical School: Virginia Commonwealth University (2004)
  • Board Certification: American Board of Internal Medicine, Gastroenterology
    MedStar Health Providers participate with a wide range of health insurance products. We accept self-pay patients and the insurances plans listed below. This list is not comprehensive, it is updated periodically and is subject to change. If you do not see your health insurance plan or product listed, or if you have any questions regarding MedStar Health’s participation with your health plan, please contact your health plan to verify participation with our providers.

    Since the MedStar Health providers span the District of Columbia, Maryland and Virginia regions, our participation with DC, Maryland and Virginia Medical Assistance programs varies by provider group. Please contact your MedStar Physician’s Office to assist with verifying Medical Assistance participation. If you are enrolled in a Medicaid Managed Care Organization, please contact your Medicaid health plan to verify participation.

Practice Locations
  • 3800 Reservoir Road Northwest
    Building 2
    Washington, DC 20007
    View Map

    Phone: 202-444-8541
    Fax: 877-303-1462

Member of Medical Staff
  • MedStar Washington Hospital Center
  • MedStar Georgetown University Hospital
  • Washingtonian Top Doctor Award, 2020
  • Fellow, American Gastroenterology Association, 2020
  • Fellow, American College of Gastroenterology, 2018
  • Gastroenterology Fellows Award for Excellence in Teaching, 2015
  • American Gastroenterological Association's Bridges to Excellence Program, 2014
  • Commitment to Patient Care, VA Medical Center, 2012