Marylyn Virginia Grondin, M.D.
Gastroenterology Physician · Portsmouth, NH
Marylyn Virginia Grondin, M.D. is a gastroenterology physician with a practice address in Portsmouth, New Hampshire, and NPI 1841266327, issued on Feb 24, 2006. Check the license (New Hampshire 8703, as entered in NPPES) on the New Hampshire Board of Medicine; the Medicare figures below come from public CMS files.
- Name
- Marylyn Virginia Grondin
- Credential
- M.D.
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License number
- 8703 NH
Self-reported in NPPES; status is on the state search - Practice location
- 330 Borthwick Ave, Portsmouth, NH 03801
- Phone
- (603) 433-2488
- Enumerated
- Feb 24, 2006
- Record last updated
- Feb 13, 2012 (not updated in 14 years: call before relying on the address or phone)
- Fax
- (603) 433-4649
- Medicare enrollment
- Enrolled (PECOS I20040922000401); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 110 in New Hampshire → Look up another NPI →
Also registered at 330 Borthwick Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Kulli Barrett, M.D.Nephrology Physician1437140209
- Lisa Benton, D.O.Pediatrics Physician1437367471
- Andrew Breen, M.D.Pediatrics Physician1861583106
- Brigette Brock, PA-CMedical Physician Assistant1871621185
- Daniel Brown, M.D.Pediatrics Physician1487742912
- Jaclyn Carter, PAPhysician Assistant1760041784
Verify Marylyn Virginia Grondin in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersNew Hampshire Board of Medicine
Search for license 8703Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
38% fewer Medicare Part D claims than the average gastroenterology physician in 2024
504 Medicare Part D claims for 144 beneficiaries, against an average of 811 among the 16,445 providers of this specialty who prescribed in Part D. Brand-name drugs were 15% of claims.
Most prescribed
- Pantoprazole Sodium127 claims
- Omeprazole87 claims
- Famotidine50 claims
- Linzess35 claims
- Ondansetron Odt21 claims
- Dicyclomine Hcl17 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
No measured MIPS final score for 2023
CMS assigned the neutral MIPS final score of 75 without scoring Quality, Cost, Promoting Interoperability or Improvement Activities. It is an administrative threshold, so PlainDoctor does not compare it with measured clinicians.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $413.49
8 payments; by number, the most common kind was food and beverage; the largest payer was Phathom Pharmaceuticals, Inc. The 13,350 providers of this specialty with any payment received $5,015.95 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- Atlantic Digestive Specialists PLLCPortsmouth, NH
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Marylyn Virginia Grondin among 110 gastroenterology physician records in New Hampshire
Marylyn Virginia Grondin, M.D. is one of 110 gastroenterology physician records with a practice address in New Hampshire. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 14% of them.
- NPI issued2006 · 14% of these records are older, 42% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 73% of these records are
- Graduated1978 · median 2002 among the 80 with a school on file
- Record last updated2012 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RG0100X and a New Hampshire practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gastroenterology Physician providers in New Hampshire
There are 110 gastroenterology physician records in New Hampshire.
All 110 in New Hampshire → Every provider in Portsmouth → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Khushboo Munot, MDPortsmouth, NH 038011487932885
- Soumil Patwardhan, M.D.Portsmouth, NH 038011891101374
- Chad Cabral, D.O.Exeter, NH 038331427226448
- Thomas Liu, M.D.Exeter, NH 038331245270255
- Melanie Pascal, MDExeter, NH 038331982193587
- Thomas Sherman, MDExeter, NH 038331639174451
- Hillary Tompkins, MDExeter, NH 038331093836157
- David Flavin, MDSomersworth, NH 038431194722454
Common questions
What is Marylyn Virginia Grondin, M.D.'s NPI number?
Marylyn Virginia Grondin, M.D.'s National Provider Identifier (NPI) is 1841266327, issued on Feb 24, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Marylyn Virginia Grondin, M.D. located?
The NPPES record lists a practice address at 330 Borthwick Ave, Portsmouth, NH, 03801. Phone: (603) 433-2488. Providers update this record themselves, so call before visiting.
How can I verify Marylyn Virginia Grondin, M.D.'s license?
NPPES lists New Hampshire license number 8703, as entered by the provider. Search the New Hampshire Board of Medicine at https://www.oplc.nh.gov/board-medicine. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Marylyn Virginia Grondin, M.D. prescribe under Medicare Part D?
In 2024, Marylyn Virginia Grondin, M.D. had 504 Medicare Part D claims for 144 beneficiaries; the average among gastroenterology physician prescribers was 811. Part D covers Medicare prescriptions only.
What is Marylyn Virginia Grondin, M.D.'s MIPS final score?
CMS assigned the neutral MIPS final score of 75 for 2023 without scoring any category, so it is not a measured result.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.