Milton Jack Grunzweig, M.D.
Internal Medicine Physician · Brooklyn, NY
Milton Jack Grunzweig, M.D. is an internal medicine physician with a practice address in Brooklyn, New York, and NPI 1528030020, issued on Feb 7, 2006. Check the license (New York 171780, as entered in NPPES) on the NYS Education Department, Office of the Professions; the Medicare figures below come from public CMS files.
- Name
- Milton Jack Grunzweig
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 171780 NY
Self-reported in NPPES; status is on the state search - Practice location
- 2000 Ocean Ave, Brooklyn, NY 11230
- Phone
- (718) 769-7900
- Enumerated
- Feb 7, 2006
- Record last updated
- Apr 24, 2008 (not updated in 18 years: call before relying on the address or phone)
- Fax
- (718) 743-4219
- Medicaid ID
- 01397819 NY
- Medicare enrollment
- Enrolled (PECOS I20050125001143); accepts Medicare assignment
- Medical or professional school
- State University Of New York Downstate Medical Center, 1986
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 12,067 in New York → Look up another NPI →
Also registered at 2000 Ocean Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Tamara Kakheladze, TAMARA KAKHELADZESpecialist1093189995
Verify Milton Jack Grunzweig in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersNYS Education Department, Office of the Professions
Search for license 171780Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
2.1 times the Medicare Part D claims of the average internal medicine physician in 2024
6,669 Medicare Part D claims for 406 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 9% of claims. 50 claims were for opioids.
Most prescribed
- Amlodipine Besylate596 claims
- Losartan Potassium361 claims
- Metoprolol Succinate305 claims
- Atorvastatin Calcium298 claims
- Gabapentin225 claims
- Metformin Hcl209 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 MIPS final score for 2023 (Medicare payment program): 93.5 of 100
The Merit-based Incentive Payment System score is reported for this clinician. 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; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $22.88
1 payment: food and beverage; the largest payer was Lilly USA, LLC. The 50,334 providers of this specialty with any payment received $1,303.06 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
- North Shore Medical Group OF The Mount Sinai School OF MedicineBrooklyn, NY
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Milton Jack Grunzweig among 12,067 internal medicine physician records in New York
Milton Jack Grunzweig, M.D. is one of 12,067 internal medicine physician records with a practice address in New York. 79% 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 8% of them.
- NPI issued2006 · 8% of these records are older, 53% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 60% of these records are
- Graduated1986 · median 2002 among the 7,221 with a school on file
- Record last updated2008 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a New York practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
1,497 internal medicine physician records list a practice address in Brooklyn
They are 1,497 of the 64,057 NPPES records with a practice address in Brooklyn, and 12,067 internal medicine physician records in New York.
All 12,067 in New York → Every provider in Brooklyn → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
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- Fredy Friedman, M.D.Brooklyn, NY 112301295797686
- Nezhat Hashemi, MDBrooklyn, NY 112301548256258
- Onyekachi Ifudu, MDBrooklyn, NY 112301073551966
- Aleksandr Ilyayev, M.D.Brooklyn, NY 112301962478438
- Tatyana Ingberman, M.D.Brooklyn, NY 112301962407106
Common questions
What is Milton Jack Grunzweig, M.D.'s NPI number?
Milton Jack Grunzweig, M.D.'s National Provider Identifier (NPI) is 1528030020, issued on Feb 7, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Milton Jack Grunzweig, M.D. located?
The NPPES record lists a practice address at 2000 Ocean Ave, Brooklyn, NY, 11230. Phone: (718) 769-7900. Providers update this record themselves, so call before visiting.
How can I verify Milton Jack Grunzweig, M.D.'s license?
NPPES lists New York license number 171780, as entered by the provider. Search the NYS Education Department, Office of the Professions at https://www.op.nysed.gov/services/verifications/online-verification-searches. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Milton Jack Grunzweig, M.D. prescribe under Medicare Part D?
In 2024, Milton Jack Grunzweig, M.D. had 6,669 Medicare Part D claims for 406 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is Milton Jack Grunzweig, M.D.'s MIPS final score?
The 2023 MIPS final score is 93.5 of 100. 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.