Atlantic Digestive Specialists

Helping people inside & out

  • Our Physicians
    • Aristotle J. Damianos, MD
    • Roger M. Epstein, MD
    • Brian H. Hyett, MD
    • Sukeerti Kesar, MD
    • Jennifer Lewis, MD
    • Sean P. Lynch, MD
    • William E. Maher, MD
    • Khushboo Munot, MD
    • Robert A. Ruben, MD
    • Sonya Alyea, APRN
    • Shelby Menard, APRN
    • Alyssa Young, APRN
    • Robert Ketchum, PA
    • Kathy Gibson, PA
    • Kerry Loan, PA
    • Rachel Whitman, PA
    • Jenna Adams, FNP
  • Conditions
    • Acid Reflux
    • Eosinophilic Esophagitis
    • Irritable Bowel Syndrome (IBS)
    • Barrett’s Esophagus
    • Food Allergies
    • Lactose Intolerance
    • Celiac Disease
    • Esophageal Diseases
    • Liver Disease
    • Cirrhosis
    • Gallstones
    • Nausea/Vomiting
    • C. Difficile Infection (C. diff)
    • Gastroesophageal Reflux (GERD)
    • Obesity
    • Colorectal Cancer
    • GI Infections
    • Pancreatitis
    • Constipation
    • Heartburn
    • Peptic Ulcers
    • Crohn’s Disease
    • Hemorrhoids
    • Polyps
    • Diarrhea
    • Hepatitis
    • Ulcerative Colitis
    • Diverticulitis
    • Inflammatory Bowel Disease (IBD)
  • Procedures
    • Bacterial Overgrowth Breath Test (SIBO)
    • Colon Cancer Screening
    • Colonoscopy
    • Endoscopic Retrograde Cholangiopancreatography
    • Endoscopic Ultrasound (EUS)
    • Esophageal Manometry
    • Esophagogastroduodenoscopy
    • Helicobacter Pylori Breath Test
    • Lactose Intolerance Breath Test
    • Liver Biopsy
    • pH Probe Placement – Impedance
    • Photodynamic Therapy
    • Radiofrequency Ablation of Barrett’s Esophagus
    • Video Capsule Endoscopy
  • Prep Instructions
    • Colonoscopy Preparations
      • Gatorade Miralax Colon Prep Instructions
      • Mag Citrate Colon Prep Instructions
      • Moviprep Colon Prep Instructions
      • Nulytely Colon Prep Instructions
      • 5 Day Miralax/Nulytely Prep Instructions
      • OSMO Pill Colon Prep Instructions
      • Prepopik Split-Dose Colon Prep Instructions
      • Suprep Split-Dose Colon Prep Instructions
    • Sigmoidoscopy Preparations
      • Sigmoidoscopy Hospital Prep Instructions
      • Sigmoidoscopy In-Office Prep Instructions
    • Upper Endoscopy Preparations
      • Esophageal Manometry Prep Instructions
      • Upper Endoscopy Hospital Prep Instructions
      • Upper Endoscopy In-Office Prep Instructions
    • Other Preparations
      • H-Pylori Breath Test Prep Instructions
      • Lactose Tolerance Testing Prep Instructions
      • Outpatient Liver Biopsy Prep Instructions
  • For Patients
    • Patient Portal
    • Patient Forms
    • Frequently Asked Questions
    • Colorectal Cancer Screening Guidelines
    • Insurance Accepted
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  • Pay Your Bill

Marylyn V. Grondin, MD

Marylyn V. Grondin, MD

Marylyn V. Grondin, MD

Dr. Marylyn V. Grondin received her degree in Medicine from LaSalle University and a Clinical Certificate from the College of Medicine and Dentistry of New Jersey. She completed her internship and residency at Bridgeport Hospital, an affiliate of Yale University Medical School. Dr. Grondin completed her fellowship in Gastroenterology at West Virginia University School of Medicine, where she continued on staff there as an Assistant Professor for three years. She established herself in private practice in the Seacoast area in 1992. Dr. Grondin is also a Clinical Instructor of Medicine at Harvard Medical School and is board certified in Internal Medicine and Gastroenterology.

Office In:

Portsmouth, NH

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