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Zachary Marwil, MD

Board Certified Gastroenterologist in Wantagh and Malverne, NY

Zachary Marwil, MD

About Dr. Marwil

Zachary Marwil, MD, is a highly respected and sought-after gastroenterologist on Long Island. Dr. Marwil is a partner at Gastrointestinal Specialists of Long Island (GISLI) and also serves as the managing director at the Northwell Health Endoscopy Center of Long Island. He is board-certified in both gastroenterology and internal medicine.

Dr. Marwil attended the University of Michigan as an undergraduate and earned his Doctor of Medicine from St. George’s University School of Medicine.

Dr. Marwil completed his residency in internal medicine at the State University of New York (SUNY) Downstate Medical Center, where he also had the honor of serving as the chief resident in the department of medicine. He continued his training as a fellow and then as chief fellow in the division of gastroenterology and hepatology at SUNY Downstate Medical Center.

Both during his post-graduate training and as an attending, Dr. Marwil has authored several research abstracts and journal articles. His findings have been published in peer-reviewed journals and presented at national meetings. 

Having held several teaching positions, Dr. Marwil is currently on faculty as an Assistant Professor at the Zucker School of Medicine at Hofstra. He is a member of the American College of Gastroenterology, the American Society of Gastrointestinal Endoscopy, and the New York Society for Gastroenterology and Endoscopy.

Dr. Marwil takes great pride in offering state-of-the-art gastroenterology care for people of all ages and strives to treat each patient with the care and empathy they deserve. When not in the office, Dr. Marwil stays active through mountain biking, skiing, golf, and tennis. He mostly enjoys spending time with his wife and two daughters.