Wei-Fang Ko, M.D.
Gastroenterology Physician · Castro Valley, CA
Wei-Fang Ko, M.D. is a gastroenterology physician with a practice address in Castro Valley, California, and NPI 1417068081, issued on Aug 31, 2006. Check the license (California A62022, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Wei-Fang Ko
- Credential
- M.D.
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License number
- A62022 CA
Self-reported in NPPES; status is on the state search - Practice location
- 19845 Lake Chabot RD, Castro Valley, CA 94546
- Phone
- (510) 537-4415
- Enumerated
- Aug 31, 2006
- Record last updated
- Aug 1, 2022
- Medicare enrollment
- Enrolled (PECOS I20100907000347); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 2,140 in California → Look up another NPI →
Also registered at 19845 Lake Chabot RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Jane Eversole, PT, MAPhysical Therapist1730177908
- Vishal Ghevariya, M.D.Gastroenterology Physician1043519531
- Murray Gould, M.D.Obstetrics & Gynecology Physician1619985025
- Peter Hooberman, M.D.Gastroenterology Physician1710098298
- Amber Jones, D.O., M.P.H.Trauma Surgery Physician1265787659
- Zev Kahn, M.D.Plastic Surgery within the Head & Neck (Otolaryngology) Physician1356310502
Verify Wei-Fang Ko in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A62022Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
26% fewer Medicare Part D claims than the average gastroenterology physician in 2024
599 Medicare Part D claims for 370 beneficiaries, against an average of 811 among the 16,445 providers of this specialty who prescribed in Part D. Brand-name drugs were 29% of claims.
Most prescribed
- Sod Sulf-Potass Sulf-Mag Sulf300 claims
- Omeprazole68 claims
- Pantoprazole Sodium44 claims
- Vemlidy30 claims
- Mesalamine19 claims
- Peg 3350-Electrolyte16 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 MIPS final score for 2023 (Medicare payment program): 80.9 of 100
The Merit-based Incentive Payment System score is reported for this clinician. 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; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- Gastroenterology Specialists Medical Group Inc A Medical CorporationCastro Valley, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Wei-Fang Ko among 2,140 gastroenterology physician records in California
Wei-Fang Ko, M.D. is one of 2,140 gastroenterology physician records with a practice address in California. 83% 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 7% of them.
- NPI issued2006 · 7% of these records are older, 48% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 72% of these records are
- Graduated1986 · median 2002 among the 1,538 with a school on file
- Record last updated2022 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RG0100X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gastroenterology Physician providers in California
There are 2,140 gastroenterology physician records in California.
All 2,140 in California → Every provider in Castro Valley → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Satya Allaparthi, MDCastro Valley, CA 945461699960815
- Vishal Ghevariya, M.D.Castro Valley, CA 945461043519531
- Peter Hooberman, M.D.Castro Valley, CA 945461710098298
- Stephen Lee, M.D.Castro Valley, CA 945461538261805
- Jeffrey Singerman, M.D.Castro Valley, CA 945461932325446
- Dina Ezzeddine, M.D.Lafayette, CA 945491598749715
- Christopher Entwisle, M.D.Livermore, CA 945501841256963
- Ru Min Lee, M.D.Livermore, CA 945501225413719
Common questions
What is Wei-Fang Ko, M.D.'s NPI number?
Wei-Fang Ko, M.D.'s National Provider Identifier (NPI) is 1417068081, issued on Aug 31, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Wei-Fang Ko, M.D. located?
The NPPES record lists a practice address at 19845 Lake Chabot RD, Castro Valley, CA, 94546. Phone: (510) 537-4415. Providers update this record themselves, so call before visiting.
How can I verify Wei-Fang Ko, M.D.'s license?
NPPES lists California license number A62022, 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 Wei-Fang Ko, M.D. prescribe under Medicare Part D?
In 2024, Wei-Fang Ko, M.D. had 599 Medicare Part D claims for 370 beneficiaries; the average among gastroenterology physician prescribers was 811. Part D covers Medicare prescriptions only.
What is Wei-Fang Ko, M.D.'s MIPS final score?
The 2023 MIPS final score is 80.9 of 100. 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.