Mark H. Johnston, MD, FACP, FACG, AGAF
2112 Harrisburg Pike, Suite 202 Lancaster, PA 17601
Specialty: Abnormal LFTs, Anemia, C. Difficile (C. Diff), Celiac Disease, Cirrhosis, Colitis, Constipation, Crohn's Disease, Diarrhea, Diverticulitis, Eosinophilic Esophagitis, Esophagitis, Fatty Liver, Gastroparesis, GERD, Hiatal Hernia, Irritable Bowel Syndrome (IBS), Pancreatitis, Primary Biliary Cirrhosis, Swallowing Diseases (Dysphagia), Ulcerative Colitis, Ulcers
Gender: Male
Locations
Doctors Office: This is where you go for regular check-ups and consultations.
Endoscopy Center: This is where you go for medical procedures, including colonoscopies, ultrasounds, studies, and more.
Lancaster
Suite 202
Lancaster, PA 17601
Doctors Office: This is where you go for regular check-ups and consultations.
Endoscopy Center: This is where you go for medical procedures, including colonoscopies, ultrasounds, studies, and more.
MidAtlantic Endoscopy 1
Suite 100
Lancaster, PA 17601
Doctors Office: This is where you go for regular check-ups and consultations.
Endoscopy Center: This is where you go for medical procedures, including colonoscopies, ultrasounds, studies, and more.
MidAtlantic Endoscopy 2
Ephrata, PA 17522
Meet Mark H. Johnston, MD, FACP, FACG, AGAF
Dr. Johnston earned his MD at Hahnemann University. He completed his Residency at Naval Medical Center Portsmouth and his Fellowship in Gastroenterology at National Naval Medical Center, Bethesda, MD.
He is former Chief of Gastroenterology at the National Naval Medical Center, Bethesda, MD, and retired as a Navy Captain in 2005. He has treated numerous members of Congress, the Supreme Court and White House.
Dr. Johnston is board certified in Internal Medicine and Gastroenterology and is a Fellow of the American College of Physicians, American College of Gastroenterology and Fellow of the American Gastroenterological Association.
He has been practicing gastroenterology in Lancaster County since 2005.
He is the author of numerous publications and is internationally known for his expertise in esophageal disease. He has several U.S. Patents for his invention of CryoSpray Ablation Therapy. This technique uses a spray of liquid nitrogen to treat cancerous and precancerous conditions of the esophagus including Barrett’s Esophagus and esophageal cancer. He has spoken nationally and internationally in his areas of research: GERD, Barrett’s Esophagus and esophageal cancer.
He has privileges at Penn Medicine Lancaster General Hospital.
He and his wife live in Lancaster. They have three children; two sons who are active-duty medical officers in the Navy and a daughter who is a Physician Assistant. In his free time, he enjoys spending time with his family, the outdoors, hiking and sailing. He has led and served in over 30 medical mission trips to Kenya, China and Albania.
Medical Education
Hahnemann University
Residency
Portsmouth Naval Medical Center
Fellowship
National Naval Medical Center