John C. Koumas, D.O.
Family Medicine Physician · West Covina, CA
John C. Koumas, D.O. is a family medicine physician with a practice address in West Covina, California, and NPI 1134111958, issued on Aug 17, 2005. Check the license (California 20A5515, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- John C. Koumas
- Credential
- D.O.
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License number
- 20A5515 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1135 S Sunset Ave Ste 200, West Covina, CA 91790
- Phone
- (626) 732-8390
- Enumerated
- Aug 17, 2005
- Record last updated
- Feb 1, 2024
- Medicare enrollment
- Enrolled (PECOS I20041020001393); accepts Medicare assignment
- Medical or professional school
- College Of Osteo Med Of The Pacific At Pomona, 1987
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 17,133 in California → Look up another NPI →
Also registered at 1135 S Sunset Ave Ste 200
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify John C. Koumas in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A5515Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
8% more Medicare Part D claims than the average family medicine physician in 2024
3,834 Medicare Part D claims for 422 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims.
Most prescribed
- Amlodipine Besylate240 claims
- Atorvastatin Calcium232 claims
- Metformin Hcl204 claims
- Levothyroxine Sodium192 claims
- Losartan Potassium176 claims
- Lisinopril114 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 practice group's MIPS final score for 2023 (Medicare payment program): 79.3 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. 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, group reporting; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $25.00
1 payment: food and beverage; the largest payer was GlaxoSmithKline, LLC. The 55,478 providers of this specialty with any payment received $902.55 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 2 group practices
- Emanate Health Medical Care FoundationWest Covina, CA
- Lake Forest Medical Group, Inc.Lake Forest, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
John C. Koumas among 17,133 family medicine physician records in California
John C. Koumas, D.O. is one of 17,133 family medicine physician records with a practice address in California. 81% 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, 94% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 62% of these records are
- Graduated1987 · median 2005 among the 10,652 with a school on file
- Record last updated2024 · 58% 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 California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
69 family medicine physician records list a practice address in West Covina
They are 69 of the 2,450 NPPES records with a practice address in West Covina, and 17,133 family medicine physician records in California.
All 17,133 in California → Every provider in West Covina → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- Fe Advincula, M.D.West Covina, CA 917901235162272
- Melody Angeles-Riparip, M.D.West Covina, CA 917901093752248
- Van Duong, M.D.West Covina, CA 917901497705289
- Teresita Belen Gan, MDWest Covina, CA 917901114028727
- Zaida Obeso, M.D.West Covina, CA 917901881790616
- Jose Pilpa, MDWest Covina, CA 917901760439012
- Adriana Pollak Lazzaro, DOWest Covina, CA 917901306923974
- Elise Pomerance, M.D.West Covina, CA 917901568569606
Common questions
What is John C. Koumas, D.O.'s NPI number?
John C. Koumas, D.O.'s National Provider Identifier (NPI) is 1134111958, issued on Aug 17, 2005. An NPI identifies a provider in billing; it is not a license.
Where is John C. Koumas, D.O. located?
The NPPES record lists a practice address at 1135 S Sunset Ave Ste 200, West Covina, CA, 91790. Phone: (626) 732-8390. Providers update this record themselves, so call before visiting.
How can I verify John C. Koumas, D.O.'s license?
NPPES lists California license number 20A5515, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does John C. Koumas, D.O. prescribe under Medicare Part D?
In 2024, John C. Koumas, D.O. had 3,834 Medicare Part D claims for 422 beneficiaries; the average among family medicine physician prescribers was 3,544. Part D covers Medicare prescriptions only.
What is John C. Koumas, D.O.'s MIPS final score?
The 2023 MIPS final score is 79.3 of 100, reported for the practice group. 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.