Isaac Anton Fonken, M.D.
Family Medicine Physician · Tacoma, WA
Isaac Anton Fonken, M.D. is a family medicine physician with a practice address in Tacoma, Washington, and NPI 1538665542, issued on Mar 30, 2018. Check the license (Washington MD.MD.61669853, as entered in NPPES) on the Washington Medical Commission; the Medicare figures below come from public CMS files.
- Name
- Isaac Anton Fonken
- Credential
- M.D.
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License numbers
- MD.MD.61669853 WA
101180 MT
Self-reported in NPPES; status is on the state search - Practice location
- 1112 6TH Ave, Tacoma, WA 98405
- Phone
- (253) 792-6680
- Enumerated
- Mar 30, 2018
- Record last updated
- Sep 4, 2025
- Fax
- (253) 403-2915
- Medicare enrollment
- Enrolled (PECOS I20250730003885); accepts Medicare assignment
- Medical or professional school
- University Of Colorado School Of Medicine, Aurora, 2018
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 5,534 in Washington → Look up another NPI →
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A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify Isaac Anton Fonken in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWashington Medical Commission
Search for license MD.MD.61669853Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
30% fewer Medicare Part D claims than the average family medicine physician in 2024
2,483 Medicare Part D claims for 82 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. 58 claims were for opioids.
Most prescribed
- Levothyroxine Sodium117 claims
- Losartan Potassium111 claims
- Jardiance110 claims
- Gabapentin87 claims
- Eliquis84 claims
- Sertraline Hcl77 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 2 group practices
- Multicare Health SystemTacoma, WA
- Yellowstone City-County Health DeptBillings, MT
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Isaac Anton Fonken among 5,534 family medicine physician records in Washington
Isaac Anton Fonken, M.D. is one of 5,534 family medicine physician records with a practice address in Washington. 73% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2018, is newer than 82% of them.
- NPI issued2018 · 82% of these records are older, 15% newer
- In a Medicare fileYes · 73% of these records are
- In the CMS Doctors and Clinicians fileYes · 60% of these records are
- Graduated2018 · median 2009 among the 3,294 with a school on file
- Record last updated2025 · 57% 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 Washington practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
363 family medicine physician records list a practice address in Tacoma
They are 363 of the 13,715 NPPES records with a practice address in Tacoma, and 5,534 family medicine physician records in Washington.
All 5,534 in Washington → Every provider in Tacoma → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- Michael Bateman, MDTacoma, WA 984051215900279
- Camela Billick, MDTacoma, WA 984051275519944
- Keith Demirjian, MDTacoma, WA 984051447223417
- Raymond Dilworth, MDTacoma, WA 984051285607150
- Mark Doane, MDTacoma, WA 984051902836935
- Stephen Hillis, MDTacoma, WA 984051356314967
- Martin Iversen, M.D.Tacoma, WA 984051427036581
- James Lenhart, M.D.Tacoma, WA 984051619955424
Common questions
What is Isaac Anton Fonken, M.D.'s NPI number?
Isaac Anton Fonken, M.D.'s National Provider Identifier (NPI) is 1538665542, issued on Mar 30, 2018. An NPI identifies a provider in billing; it is not a license.
Where is Isaac Anton Fonken, M.D. located?
The NPPES record lists a practice address at 1112 6TH Ave, Tacoma, WA, 98405. Phone: (253) 792-6680. Providers update this record themselves, so call before visiting.
How can I verify Isaac Anton Fonken, M.D.'s license?
NPPES lists Washington license number MD.MD.61669853, as entered by the provider. Search the Washington Medical Commission at https://wahelms.my.site.com/s/license-search. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Isaac Anton Fonken, M.D. prescribe under Medicare Part D?
In 2024, Isaac Anton Fonken, M.D. had 2,483 Medicare Part D claims for 82 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.