Overview
Mark Johnston is a Gastroenterologist in Lancaster, Pennsylvania. Dr. Johnston is rated as an Experienced provider by MediFind in the treatment of Childhood Pancreatitis. His top areas of expertise are Barrett Esophagus, Swallowing Difficulty, Painful Swallowing, Gastrectomy, and Endoscopy. Dr. Johnston is currently accepting new patients.
Insurance
Accepted insurance can change. Please verify directly with the provider.
Accepted insurance plans:
- EPO
- HMO
- POS
- PPO
- EPO
- HMO
- POS
- PPO
- MEDICARE PDP
- EPO
- HMO
- POS
- PPO
- INSURANCE PLAN
- MANAGED MEDICAID PLAN
- MEDICARE MAPD
- OTHER MEDICARE PART D
- PPO
- EPO
- HMO
- PPO
- INSURANCE PLAN
- MANAGED MEDICAID PLAN
- MEDICARE SNP
- OTHER MEDICARE PART D
- HMO
- POS
- PPO
- HMO
- INSURANCE PLAN
- MANAGED MEDICAID PLAN
- MEDICARE MAPD
- MEDICARE PDP
- MEDICARE SNP
- OTHER COMMERCIAL
- OTHER MEDICARE
- OTHER MEDICARE PART D
- PPO
- INSURANCE PLAN
- MANAGED MEDICAID PLAN
- MEDICARE MAPD
- MEDICARE SNP
- EPO
- HMO
- PPO
- HMO
- INDEMNITY
- POS
- PPO
- EPO
- POS
- PPO
- OTHER MANAGED MEDICAID
- OTHER MEDICAID
- STATE MEDICAID
- INSURANCE PLAN
- MANAGED MEDICAID PLAN
- MEDICARE MAPD
- MEDICARE PDP
- MEDICARE SNP
- MEDICARE-MEDICAID PLAN
- OTHER MEDICARE PART D
- EPO
- HMO
- PPO
- OTHER COMMERCIAL
- EPO
- HMO
- POS
- PPO
- EPO
- PPO
- EPO
- HMO
- INSURANCE PLAN
- MANAGED MEDICAID PLAN
- MEDICARE MAPD
- MEDICARE PDP
- MEDICARE SNP
- MEDICARE-MEDICAID PLAN
- OTHER MEDICARE
- OTHER MEDICARE PART D
Locations
2112 Harrisburg Pike, Suite 202, Lancaster, PA 17601
Additional Areas of Focus
Dr. Johnston has provided the following conditions as areas of focus. Please note that we may not have enough data to validate their experience in some of these conditions.
Asim Maqbool is a Pediatric Gastroenterologist and a Gastroenterologist in Philadelphia, Pennsylvania. Dr. Maqbool is rated as a Distinguished provider by MediFind in the treatment of Childhood Pancreatitis. His top areas of expertise are Exocrine Pancreatic Insufficiency, Childhood Pancreatitis, Chronic Pancreatitis, Hereditary Pancreatitis, and Endoscopy.
Johns Hopkins Health Care & Surgery Center - Green Spring Station, Lutherville
Vikesh Singh is a gastroenterologist who specializes in pancreatology and pancreaticobiliary endoscopy. He evaluates and treats patients with inflammatory diseases of the pancreas, including acute and chronic pancreatitis and autoimmune pancreatitis as well as the complications of these diseases. After earning his medical degree from the Johns Hopkins University School of Medicine, Dr. Singh remained at Johns Hopkins to complete residency training in internal medicine. He pursued fellowship training in gastroenterology at Brigham and Women’s Hospital, and earned a master’s degree in epidemiology from the Harvard T. H. Chan School of Public Health. He then returned to Johns Hopkins, where he completed a two-year advanced endoscopy fellowship with a focus on pancreaticobiliary endoscopy. Dr. Singh has been on the faculty at Johns Hopkins since 2008, and rose to the rank of professor in 2021. His research interests include acute and chronic pancreatitis, autoimmune pancreatitis, exocrine pancreatic insufficiency, and novel methods to evaluate and treat abdominal pain. Dr. Singh is a member of the board of directors of the National Pancreas Foundation, chair of the Pancreatic Disorders Section of the American Gastroenterological Association, a councilor for the International Association of Pancreatology and a member of the inaugural medical advisory board for the Familial Chylomicronemia Syndrome Foundation. Dr. Singh is rated as an Elite provider by MediFind in the treatment of Childhood Pancreatitis. His top areas of expertise are Exocrine Pancreatic Insufficiency, Hereditary Pancreatitis, Acute Pancreatitis, Pancreatectomy, and Endoscopy.
Maria Mascarenhas is a Pediatric Gastroenterologist and a Gastroenterologist in Philadelphia, Pennsylvania. Dr. Mascarenhas is rated as a Distinguished provider by MediFind in the treatment of Childhood Pancreatitis. Her top areas of expertise are Exocrine Pancreatic Insufficiency, Childhood Pancreatitis, Chronic Pancreatitis, DiGeorge Syndrome, and Gastrostomy.
Areas of Expertise
MediFind evaluates expertise by pulling from factors such as number of articles a doctor has published in medical journals, participation in clinical trials, speaking at industry conferences, prescribing and referral patterns, and strength of connections with other experts in their field.
Learn more about MediFind’s expert tiers
- Advanced
- Barrett EsophagusDr. Johnston isAdvanced. Learn about Barrett Esophagus.
- Benign Esophageal StrictureDr. Johnston isAdvanced. Learn about Benign Esophageal Stricture.
- ColitisDr. Johnston isAdvanced. Learn about Colitis.
- Crohn's DiseaseDr. Johnston isAdvanced. Learn about Crohn's Disease.
- EsophagitisDr. Johnston isAdvanced. Learn about Esophagitis.
- Gastroesophageal Reflux Disease (GERD)
- Experienced
- AchalasiaDr. Johnston isExperienced. Learn about Achalasia.
- Acute PancreatitisDr. Johnston isExperienced. Learn about Acute Pancreatitis.
- Alcoholic CirrhosisDr. Johnston isExperienced. Learn about Alcoholic Cirrhosis.
- AnemiaDr. Johnston isExperienced. Learn about Anemia.
- Angiodysplasia of the ColonDr. Johnston isExperienced. Learn about Angiodysplasia of the Colon.
- AscitesDr. Johnston isExperienced. Learn about Ascites.

