Granite Gastroenterology | GI Clinic & IBD Care
Gastroenterology • Manchester, NH • multiple locations locations
About
Granite State Gastroenterology is a New Hampshire-based GI clinic offering general gastrointestinal care, inflammatory bowel disease (IBD) management, esophageal motility disorders, liver disease treatment, and hepatitis C care. Headquartered in Derry with five office locations across NH (including Derry, Raymond, Windham, and Bedford). Key personnel include Gastroenterologist Managing Partner Dr. Leon McLean and Director of Operations Jennifer Marshall. They emphasize patient choice and communication, with a small team (about 13 employees). Priorities likely include IBD care, GI disorders, and liver disease, supported by a regional presence and multiple contact numbers for scheduling. If you’re seeking GI services in Manchester, note that Granite State Gastroenterology operates offices within NH communities and may serve nearby areas; for Manchester-specific GI care, confirm closest location and available IBD or liver disease specialists.
Clinic Type
Gastroenterology
Address
Bedford, NH; Londonderry, NH; Windham, NH
Phone
603-432-8802
—
Opening Hours
Not published — contact the clinic to confirm hours.
Website
Services Offered
Technology & Equipment
Team
Insurance & Payment
—
Languages Spoken
FAQs
What services does Granite State Gastroenterology offer?
Gastrointestinal care including evaluation and treatment of GI disorders, colonoscopies, upper endoscopy, PEG tube placement, liver disease care, irritable bowel syndrome, inflammatory bowel disease, esophageal disorders, hepatitis C, pancreatic disorders, and rectal diseases.
Social Media
Photos








What Patients Say
Overall sentiment across review platforms: positive
- Birdeye/Google aggregate: 5.0 out of 5 stars (aggregated based on 73 reviews across platforms) (73)
- WebMD Care: 4.5 out of 5 stars (23 ratings (8 written reviews))
Patients praise
- Staff described as welcoming, friendly, and helpful
- Providers praised for being thorough, knowledgeable, and genuinely listening to patient concerns
- Positive experiences with long-term management of chronic conditions like Crohn's disease
- Clean and professional office environment
Common complaints
- Concerns expressed regarding the knowledge level of some Physician Assistants (PAs) compared to doctors
"DR. Dainiak is the absolute rock star of Gastroentetology... he listens , i mean really listens. i’m happy to report that my crohn’s is under control."
— WebMD Care review"Dr. Horton is an excellent and thorough doctor! She listens to your questions. She answers any and all questions or concerns you may have and provides explanations and advice should you seek those too."
— Granite State Gastroenterology website"Dr. Dainiak is very nice. Unfortunately, the PA they feed me to knows almost nothing, which is concerning regarding my care."
— Yelp reviewSynthesized from public review platforms as of Jul 11, 2026 — sources: [1][2][3][4].
In the News
- Bravo pH Probe Study in Bedford, NH and Londonderry, NH | Granite State Gastroenterology — Dec 1, 2025
- IBS Awareness Month: Understanding Irritable Bowel Syndrome and ... — Apr 2, 2026
- [PDF] Icotrokinra, a targeted oral peptide that selectively blocks IL-23 — Oct 7, 2025
- Expanding Our Focus: Launching our NEW "Comprehensive IBD Care Center at GANJ" - Gastroenterology Associates of New Jersey — May 19, 2026
Information sourced from the clinic's website as of July 11, 2026.
More gastroenterology clinics in Manchester
Summary: The Elliot Hospital in Manchester, NH (part of SolutioNHealth) is a nonprofit, acute-care hospital with 296 beds and a Level II trauma center. It offers comprehensive medical services across its Elliot Health System, including the Elliot Medical Group and related centers. For GI services, contact the hospital directly or check the Elliot Health System gastroenterology department for clinics, specialists, procedures (EGD, colonoscopy), and locations (Manchester and ambulatory centers). Key contacts: customer service 603-669-5300, 603-663-4567, or 833-920-7473. Address: One Elliot Way, Manchester, NH 03103.
Gastroenterology at Catholic Medical Center (CMC) in Manchester, NH - CMC is a nonprofit, full-service acute care hospital with 330 beds (258 staffed) in Manchester, part of a larger New Hampshire health system. - Location: 100 McGregor Street, Manchester, NH 03102. Level III trauma, 24-hour ED, imaging and numerous subspecialties. - Gastroenterology services are part of CMC’s broad offerings, including subspecialties and diagnostic imaging. - Notable context: CMC hosts Norris Cotton Cancer Center services; the site has faced prior investigative scrutiny in 2022 related to surgical malpractice coverage concerns (external exposé, not specific to gastroenterology care today). - Quick facts: Nonprofit hospital, founded 1892, affiliated with a broader NH and international presence, and operates within a larger health system network. For direct gastroenterology appointments, contact main line or visit the CMC website.
Comparing your options?
See other gastroenterology clinics in Manchester, or search the full directory by insurance, ratings, and more.

