Walter J. Gruber, M.D.
Internal Medicine Physician · Midland, MI
Walter J. Gruber, M.D. is an internal medicine physician with a practice address in Midland, Michigan, and NPI 1164440277, issued on Jul 17, 2006. Check the license (Michigan WG038289, as entered in NPPES) on the Michigan Board of Medicine (LARA); the Medicare figures below come from public CMS files.
- Name
- Walter J. Gruber
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- WG038289 MI
Self-reported in NPPES; status is on the state search - Practice location
- 555 W Wackerly Street, Midland, MI 48640
- Phone
- (989) 631-8300
- Enumerated
- Jul 17, 2006
- Record last updated
- Oct 26, 2011 (not updated in 15 years: call before relying on the address or phone)
- Fax
- (989) 839-8170
- Medicaid ID
- 2096083 MI
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 5,735 in Michigan → Look up another NPI →
Verify Walter J. Gruber in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMichigan Board of Medicine (LARA)
Search for license WG038289Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
100% more Medicare Part D claims than the average internal medicine physician in 2024
6,344 Medicare Part D claims for 527 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims. 86 claims were for opioids.
Most prescribed
- Atorvastatin Calcium395 claims
- Losartan Potassium318 claims
- Amlodipine Besylate247 claims
- Levothyroxine Sodium242 claims
- Lisinopril232 claims
- Metformin Hcl Er141 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.
Walter J. Gruber among 5,735 internal medicine physician records in Michigan
Walter J. Gruber, M.D. is one of 5,735 internal medicine physician records with a practice address in Michigan. 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 10% of them.
- NPI issued2006 · 10% of these records are older, 60% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileNo · 62% of these records are
- Record last updated2011 · 54% 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 Michigan practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
37 internal medicine physician records list a practice address in Midland
They are 37 of the 2,324 NPPES records with a practice address in Midland, and 5,735 internal medicine physician records in Michigan.
All 5,735 in Michigan → Every provider in Midland → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Catherine Bodnar, MD, MPHMidland, MI 486401487791232
- Emily Hemond, MDMidland, MI 486401871120071
- Roschelle Houston, DOMidland, MI 486401780694992
- Phillip Kadaj, MDMidland, MI 486401417157165
- Teona Maghlakelidze, MDMidland, MI 486401508078023
- Michael Miller, MDMidland, MI 486401851303606
- David Nadolski, M.D.Midland, MI 486401982641098
- Suja Shenoy, M.D.Midland, MI 486401316220551
Common questions
What is Walter J. Gruber, M.D.'s NPI number?
Walter J. Gruber, M.D.'s National Provider Identifier (NPI) is 1164440277, issued on Jul 17, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Walter J. Gruber, M.D. located?
The NPPES record lists a practice address at 555 W Wackerly Street, Midland, MI, 48640. Phone: (989) 631-8300. Providers update this record themselves, so call before visiting.
How can I verify Walter J. Gruber, M.D.'s license?
NPPES lists Michigan license number WG038289, as entered by the provider. Search the Michigan Board of Medicine (LARA) at https://aca-prod.accela.com/MILARA/GeneralProperty/PropertyLookUp.aspx?isLicensee=Y&TabName=APO. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Walter J. Gruber, M.D. prescribe under Medicare Part D?
In 2024, Walter J. Gruber, M.D. had 6,344 Medicare Part D claims for 527 beneficiaries; the average among internal medicine physician prescribers was 3,176. 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.