Grier H. Merwin, M.D.
Family Medicine Physician · Dorchester, MA
Grier H. Merwin, M.D. is a family medicine physician with a practice address in Dorchester, Massachusetts, and NPI 1255378204, issued on May 31, 2006. Check the license (Massachusetts 35314, as entered in NPPES) on the Massachusetts Board of Registration in Medicine; the Medicare figures below come from public CMS files.
- Name
- Grier H. Merwin
- Credential
- M.D.
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License number
- 35314 MA
Self-reported in NPPES; status is on the state search - Practice location
- 500 Columbia Road, Dorchester, MA 02125
- Phone
- (617) 287-8000
- Enumerated
- May 31, 2006
- Record last updated
- Mar 22, 2018 (not updated in 8 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20050517000670); accepts Medicare assignment
- Medical or professional school
- Columbia University College Of Physicians And Surgeons, 1967
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 2,265 in Massachusetts → Look up another NPI →
Also registered at 500 Columbia Road
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Andrea Dandridge, FNP. MPHFamily Nurse Practitioner1760636948
Verify Grier H. Merwin in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMassachusetts Board of Registration in Medicine
Search for license 35314Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
96% fewer Medicare Part D claims than the average family medicine physician in 2024
125 Medicare Part D claims for 52 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. Brand-name drugs were 18% of claims.
Most prescribed
- Diclofenac Sodium17 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.
Bills Medicare through one group practice
- Uphams Corner Health Committee IncDorchester, MA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Grier H. Merwin among 2,265 family medicine physician records in Massachusetts
Grier H. Merwin, M.D. is one of 2,265 family medicine physician records with a practice address in Massachusetts. 80% 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, 55% newer
- In a Medicare fileYes · 80% of these records are
- In the CMS Doctors and Clinicians fileYes · 68% of these records are
- Graduated1967 · median 2006 among the 1,529 with a school on file
- Record last updated2018 · 59% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207Q00000X and a Massachusetts practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
43 family medicine physician records list a practice address in Dorchester
They are 43 of the 1,663 NPPES records with a practice address in Dorchester, and 2,265 family medicine physician records in Massachusetts.
All 2,265 in Massachusetts → Every provider in Dorchester → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- Daniel Cagua-Koo, MDDorchester, MA 021251114120656
- Elise Henricks, MDDorchester, MA 021251154392850
- Dante Lantin, MDDorchester, MA 021251598740425
- Geoffrey Modest, MDDorchester, MA 021251023002169
- Elisabeth Moths-Rebrovic, MDDorchester, MA 021251558332270
- Valerie Sanders, MDDorchester, MA 021251033175088
- Emy Chen, MDBoston, MA 021241437531332
- Michelle Dalencour, M.D.Mattapan, MA 021261073873006
Common questions
What is Grier H. Merwin, M.D.'s NPI number?
Grier H. Merwin, M.D.'s National Provider Identifier (NPI) is 1255378204, issued on May 31, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Grier H. Merwin, M.D. located?
The NPPES record lists a practice address at 500 Columbia Road, Dorchester, MA, 02125. Phone: (617) 287-8000. Providers update this record themselves, so call before visiting.
How can I verify Grier H. Merwin, M.D.'s license?
NPPES lists Massachusetts license number 35314, as entered by the provider. Search the Massachusetts Board of Registration in Medicine at https://findmydoctor.mass.gov/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Grier H. Merwin, M.D. prescribe under Medicare Part D?
In 2024, Grier H. Merwin, M.D. had 125 Medicare Part D claims for 52 beneficiaries; the average among family medicine physician prescribers was 3,544. Part D covers Medicare prescriptions only.
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.