Gregory V. Warren, MD
Nephrology Physician · Milwaukee, WI
Gregory V. Warren, MD is a nephrology physician with a practice address in Milwaukee, Wisconsin, and NPI 1649262544, issued on Aug 17, 2005. Check the license (Wisconsin 26514, as entered in NPPES) on the Wisconsin Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- Gregory V. Warren
- Credential
- MD
- Primary taxonomy
- Nephrology Physician 207RN0300X
- License number
- 26514 WI
Self-reported in NPPES; status is on the state search - Practice location
- 3120 South 27TH Street, Milwaukee, WI 53215
- Phone
- (414) 672-8282
- Enumerated
- Aug 17, 2005
- Record last updated
- Dec 9, 2021 (not updated in 5 years: call before relying on the address or phone)
- Fax
- (414) 672-8284
- Medicaid ID
- 3082990 WI
- Entity
- Type 1 · individual
8 nearest nephrology physician records → All 207 in Wisconsin → Look up another NPI →
Also registered at 3120 South 27TH Street
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Claire Fritsche, MDNephrology Physician1548252547
- Vasundhara Ganne, MDNephrology Physician1053303057
- William Kraklow, MDNephrology Physician1184616187
- Nichole Melton, APRNAdult Health Nurse Practitioner1750555363
- Kathleen Uy, MDNephrology Physician1255323259
- Paul Warren, MDNephrology Physician1487646477
Verify Gregory V. Warren in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWisconsin Medical Examining Board
Search for license 26514Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
19% fewer Medicare Part D claims than the average nephrology physician in 2024
1,193 Medicare Part D claims for 274 beneficiaries, against an average of 1,465 among the 10,986 providers of this specialty who prescribed in Part D. Brand-name drugs were 14% of claims.
Most prescribed
- Calcitriol152 claims
- Losartan Potassium104 claims
- Furosemide94 claims
- Amlodipine Besylate91 claims
- Terazosin Hcl73 claims
- Jardiance63 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.
Gregory V. Warren among 207 nephrology physician records in Wisconsin
Gregory V. Warren, MD is one of 207 nephrology physician records with a practice address in Wisconsin. 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, 89% newer
- In a Medicare fileYes · 86% of these records are
- In the CMS Doctors and Clinicians fileNo · 76% of these records are
- Record last updated2021 · 51% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RN0300X and a Wisconsin practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Nephrology Physician providers in Wisconsin
There are 207 nephrology physician records in Wisconsin.
All 207 in Wisconsin → Every provider in Milwaukee → Nephrology Physician nationwide →
The 8 nephrology physician records with the nearest ZIP codes
- Manohar Ahuja, M.D.Milwaukee, WI 532151467426064
- Amir Daniel, M.D.Milwaukee, WI 532151154313153
- William Elliott, M.D.Milwaukee, WI 532151861466161
- Claire Fritsche, MDMilwaukee, WI 532151548252547
- Vasundhara Ganne, MDMilwaukee, WI 532151053303057
- Matthew Hanna, M.D.Milwaukee, WI 532151962476531
- William Kraklow, MDMilwaukee, WI 532151184616187
- Ahmed Malik, M.D.Milwaukee, WI 532151679548135
Common questions
What is Gregory V. Warren, MD's NPI number?
Gregory V. Warren, MD's National Provider Identifier (NPI) is 1649262544, issued on Aug 17, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Gregory V. Warren, MD located?
The NPPES record lists a practice address at 3120 South 27TH Street, Milwaukee, WI, 53215. Phone: (414) 672-8282. Providers update this record themselves, so call before visiting.
How can I verify Gregory V. Warren, MD's license?
NPPES lists Wisconsin license number 26514, as entered by the provider. Search the Wisconsin Medical Examining Board at https://dsps.wi.gov/Pages/BoardsCouncils/MEB/Default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Gregory V. Warren, MD prescribe under Medicare Part D?
In 2024, Gregory V. Warren, MD had 1,193 Medicare Part D claims for 274 beneficiaries; the average among nephrology physician prescribers was 1,465. 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.