Jeffrey Karson, MD
Internal Medicine Physician · Grand Rapids, MI
Jeffrey Karson, MD is an internal medicine physician with a practice address in Grand Rapids, Michigan, and NPI 1205404597, issued on Jun 14, 2021. Check the license (Michigan 4351048542, as entered in NPPES) on the Michigan Board of Medicine (LARA); the Medicare figures below come from public CMS files.
- Name
- Jeffrey Karson
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 4351048542 MI
Self-reported in NPPES; status is on the state search - Practice location
- 100 Michigan St NE, Grand Rapids, MI 49503
- Phone
- (616) 391-3139
- Enumerated
- Jun 14, 2021
- Record last updated
- Jul 29, 2025
- Medicare enrollment
- Enrolled (PECOS I20250619001850); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 5,735 in Michigan → Look up another NPI →
Also registered at 100 Michigan St NE
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify Jeffrey Karson in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMichigan Board of Medicine (LARA)
Search for license 4351048542Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
97% fewer Medicare Part D claims than the average internal medicine physician in 2024
85 Medicare Part D claims for 29 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. 36 claims were for opioids.
Most prescribed
- Hydrocodone-Acetaminophen11 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
- Spectrum Health Primary Care PartnersGrand Rapids, MI
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Jeffrey Karson among 5,735 internal medicine physician records in Michigan
Jeffrey Karson, MD 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 2021, is newer than 83% of them.
- NPI issued2021 · 83% of these records are older, 13% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 62% of these records are
- Graduated2020 · median 2006 among the 3,564 with a school on file
- Record last updated2025 · 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).
451 internal medicine physician records list a practice address in Grand Rapids
They are 451 of the 18,005 NPPES records with a practice address in Grand Rapids, and 5,735 internal medicine physician records in Michigan.
All 5,735 in Michigan → Every provider in Grand Rapids → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Vikas Bajpai, MDGrand Rapids, MI 495031407854458
- Jayne Courts, M.D.Grand Rapids, MI 495031518931500
- Josip Divic, MDGrand Rapids, MI 495031770587305
- Mark Evenhouse, M.D.Grand Rapids, MI 495031053386367
- Robert Jarve, MDGrand Rapids, MI 495031285639161
- Rajendra Katragadda, MDGrand Rapids, MI 495031811974017
- Patricia Lagrand, MDGrand Rapids, MI 495031215931258
- Gerald Lee, MDGrand Rapids, MI 495031265437420
Common questions
What is Jeffrey Karson, MD's NPI number?
Jeffrey Karson, MD's National Provider Identifier (NPI) is 1205404597, issued on Jun 14, 2021. An NPI identifies a provider in billing; it is not a license.
Where is Jeffrey Karson, MD located?
The NPPES record lists a practice address at 100 Michigan St NE, Grand Rapids, MI, 49503. Phone: (616) 391-3139. Providers update this record themselves, so call before visiting.
How can I verify Jeffrey Karson, MD's license?
NPPES lists Michigan license number 4351048542, 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 Jeffrey Karson, MD prescribe under Medicare Part D?
In 2024, Jeffrey Karson, MD had 85 Medicare Part D claims for 29 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.