Dr. Mark C. Mattar, MD | Washington, DC | Gastroenterologist

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Dr. Mark Mattar is a gastroenterologist who specializes in diagnosing and treating conditions affecting the digestive system. He holds board certification in internal medicine from the American Board of Internal Medicine, providing him with comprehensive training in adult medicine before focusing on gastrointestinal health. Dr. Mattar communicates with patients in English.

Dr. Mattar practices at MedStar Georgetown University Hospital in Washington, DC. He focuses on treating inflammatory bowel conditions such as Crohn's disease and ulcerative colitis, as well as managing colon polyps. His procedural expertise includes performing colonoscopies and lower gastrointestinal endoscopy with sedation to ensure patient comfort during these important diagnostic procedures. Patients have given him an average rating of 3.8 out of 5 stars.

Overview based on verified provider data

accepting new patients
3.8

14 Ratings
22 insurance plans accepted
speaks English
13 written reviews
1 specialty
14 areas of expertise
1 board certification
1 hospital affiliation
1 office location
Male

14 ratings & reviews

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Showing 1 to 10 of 13 reviews

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An excellent appt!

March 28th, 2025 | Source: Partner

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Dr. Mattar is great. Very efficient and too the point but answers all questions thoroughly and with care. He is a great doc, just wish I could get in to see him more frequently as a routine Crohn's patient.

November 20th, 2024 | Source: Partner

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Very good.

January 3rd, 2024 | Source: Partner

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My problem remains unresolved

November 30th, 2023 | Source: Partner

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*Dr. Mattar didn't really explain anything at all. He was only in the room for less than 5 minutes.

March 17th, 2023 | Source: Partner

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Dr mattar is very professional and pleasant.

September 1st, 2022 | Source: Partner

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Dr. Mattar is a very knowledgeable doctor, very patience and explain and listen to the patient. His team of GI nurses and fellows very nice and caring staff. Dr. Mattar is compassionate, caring and very kind. He does not discharge the patient if not feeling complete ok. my family will recommend him.

November 19th, 2019

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Met Dr. Mattar the day i had my colonoscopy. He introduced himself to me and the others associates that would be working with him. I believe that he is easy to talk to, courteous and an excellent bedside manner.

February 12th, 2019

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Like a previous review, I found Dr. Mattar personable and friendly but also quick to not want to dig deeper to find the root cause of my symptoms (another doctor ended up figuring out some major pieces of the puzzle for me since my visit with him). In regards to follow up about future treatment, none of my calls or electronic messages were acknowledged or returned. Speaking with several others, I have found that other people have had similar experiences- he is almost impossible to communicate with. Not sure if this is a problem with Georgetown hospital and their efficiency or the doctor himself but either way, it's completely unacceptable and serious diagnoses could be delayed or missed because of this.

August 17th, 2018

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Our son's appointment with Dr. Mattar went very well, in fact, we were very impressed. However, when my son had complications and he tried to contact Dr. Mattar he never returned the calls to address the many questions my son had abut the medication, the fact that he was having extremely bad complications from his ulcerative colitis. One person from his office would answer sometimes and say to our son "I gave your message to the doctor" and that was all. We finally took our son to another local doctor because we were very concern with his situation. This was over a two-week period, by the way that our son was having bad complications. Dr. Mattar never called our son even after we parents called his office and spoke with the office manager and explained our concerns.

January 27th, 2018

MedStar Health Gastroenterology at MedStar Georgetown University Hospital

3800 Reservoir Road NW Main Building, 2nd floor, Room 2210Washington, DC 20007

Tel: (202) 444-8541

Mon8:00 am - 4:30 pm

Tue8:00 am - 4:30 pm

Wed8:00 am - 4:30 pm

Thu8:00 am - 4:30 pm

Fri8:00 am - 4:30 pm

SatClosed

SunClosed


Dr. Mark Christopher Mattar, MD	Ji Soo Choi, APRN	Dr. Turki Hamid S Alkully, MD	Dr. Zahid W Butt, MD
Gastroenterology	Gastroenterology	Internal Medicine	Gastroenterology
Accepts New Patients	Accepts New Patients
3.8 (14 Ratings)	0 (0 Ratings)	0 (0 Ratings)	1 (1 Rating)
		18 Years of Experience
No Virtual Visit Option	Virtual Visit Available	No Virtual Visit Option	No Virtual Visit Option
Speaks English	Speaks English
Washington , DC	SACRAMENTO , CA	Washington , DC	Columbia , MD
	Med School: New York University	Med School: Taibah University College Of Medicine
Current Profile	View Profile	View Profile	View Profile

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Gastroenterology

Abdominal Pain
Acid Reflux Disease (Gastroesophageal Reflux / GERD)
Acid Reflux Disease (GERD)
Celiac Disease
Colon Cancer
Colonoscopy
Constipation
Gastrointestinal Cancer
Hemorrhoids
Hepatitis
Inflammatory Bowel Diseases (IBD)
Irritable Bowel Syndrome (IBS)
Probiotics
Ulcerative Colitis

BOARD CERTIFICATIONS

American Board of Internal Medicine

Internal medicine

MEDICAL LICENSE

Medical Doctor, District Of Columbia, 2027, Active

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Is Dr. Mark Mattar accepting new patients?: Dr. Mark Mattar is accepting new patients on Vitals. View Dr. Mark Mattar's profile on Vitals to make an appointment.
Does Dr. Mark Mattar accept my insurance?: You can see the insurance plans that Dr. Mark Mattar accepts on their Vitals profile.
What languages does Dr. Mark Mattar speak?: Dr. Mark Mattar speaks English.
Which hospitals is Dr. Mark Mattar affiliated with?: Dr. Mark Mattar is affiliated with Medstar Georgetown University Hospital.
Where is Dr. Mark Mattar's office located?: Dr. Mark Mattar's office is located at 3800 Reservoir Road NW Main Building, 2nd floor, Room 2210, Washington, DC, 20007.

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