James W. O'Brien, MD
Gastroenterology Physician · Manchester, CT
James W. O'Brien, MD is a gastroenterology physician with a practice address in Manchester, Connecticut, and NPI 1841275252, issued on Dec 8, 2005. Check the license (Connecticut 035189, as entered in NPPES) on the Connecticut Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- James W. O'Brien
- Credential
- MD
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License numbers
- 035189 CT
MD-19477 HI
Self-reported in NPPES; status is on the state search - Practice location
- 353 Main St, Manchester, CT 06040
- Phone
- (860) 649-3477
- Enumerated
- Dec 8, 2005
- Record last updated
- May 1, 2025
- Medicaid ID
- 001351890 CT
- Medicare enrollment
- Enrolled (PECOS I20180625002009); accepts Medicare assignment
- Medical or professional school
- Duke University School Of Medicine, 1991
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 336 in Connecticut → Look up another NPI →
Also registered at 353 Main St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Khadijat Balogun, M.DGastroenterology Physician1124310743
- Peter Buch, MDGastroenterology Physician1124098199
- Madelyn CzekalskiMedical Physician Assistant1316658222
- Irm Khan, P.A.Medical Physician Assistant1992924906
- Nishita Mayette, FNP-CFamily Nurse Practitioner1588428973
- Rohit Singhania, M.D.Gastroenterology Physician1457664500
Verify James W. O'Brien in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersConnecticut Medical Examining Board
Search for license 035189Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
59% fewer Medicare Part D claims than the average gastroenterology physician in 2024
333 Medicare Part D claims for 165 beneficiaries, against an average of 811 among the 16,445 providers of this specialty who prescribed in Part D. Brand-name drugs were 10% of claims.
Most prescribed
- Pantoprazole Sodium92 claims
- Peg 3350-Electrolyte52 claims
- Omeprazole24 claims
- Famotidine22 claims
- Ciprofloxacin Hcl21 claims
- Creon15 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.
The practice group's MIPS final score for 2023 (Medicare payment program): 86.2 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
2 hospital affiliations
- Straub Clinic And HospitalHonolulu, HI · Acute Care Hospitals4 of 5 stars
- Hilo Benioff Medical CenterHilo, HI · Acute Care Hospitals3 of 5 stars
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through); hospitals matched to CMS Hospital General Information (Care Compare) (data.cms.gov). Star ratings are CMS hospital ratings, not ratings of this provider.
James W. O'Brien among 336 gastroenterology physician records in Connecticut
James W. O'Brien, MD is one of 336 gastroenterology physician records with a practice address in Connecticut. 86% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 85% newer
- In a Medicare fileYes · 86% of these records are
- In the CMS Doctors and Clinicians fileYes · 76% of these records are
- Graduated1991 · median 2001 among the 255 with a school on file
- Record last updated2025 · 69% 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 Connecticut practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gastroenterology Physician providers in Connecticut
There are 336 gastroenterology physician records in Connecticut.
All 336 in Connecticut → Every provider in Manchester → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Khadijat Balogun, M.DManchester, CT 060401124310743
- Peter Buch, MDManchester, CT 060401124098199
- Rohit Singhania, M.D.Manchester, CT 060401457664500
- Robert Schwartz, M.D.Manchester, CT 060421700861473
- Joseph Cappa, MDGlastonbury, CT 060331639273212
- Donna Cipolla, MDGlastonbury, CT 060331508845306
- Jeffrey Gelwan, MDGlastonbury, CT 060331619071230
- Jenna Koliani-Pace, M.D.Glastonbury, CT 060331316209141
Common questions
What is James W. O'Brien, MD's NPI number?
James W. O'Brien, MD's National Provider Identifier (NPI) is 1841275252, issued on Dec 8, 2005. An NPI identifies a provider in billing; it is not a license.
Where is James W. O'Brien, MD located?
The NPPES record lists a practice address at 353 Main St, Manchester, CT, 06040. Phone: (860) 649-3477. Providers update this record themselves, so call before visiting.
How can I verify James W. O'Brien, MD's license?
NPPES lists Connecticut license number 035189, as entered by the provider. Search the Connecticut Medical Examining Board at https://www.elicense.ct.gov/Lookup/LicenseLookup.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does James W. O'Brien, MD prescribe under Medicare Part D?
In 2024, James W. O'Brien, MD had 333 Medicare Part D claims for 165 beneficiaries; the average among gastroenterology physician prescribers was 811. Part D covers Medicare prescriptions only.
What is James W. O'Brien, MD's MIPS final score?
The 2023 MIPS final score is 86.2 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
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.