John Charles Pfeffer, M.D.
Obstetrics & Gynecology Physician · Modesto, CA
John Charles Pfeffer, M.D. is an obstetrics & gynecology physician with a practice address in Modesto, California, and NPI 1851456602, issued on Dec 22, 2006. Check the license (California C400620, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- John Charles Pfeffer
- Credential
- M.D.
- Primary taxonomy
- Obstetrics & Gynecology Physician 207V00000X
- License number
- C400620 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1541 Florida Ave Ste 304, Modesto, CA 95350
- Phone
- (209) 522-1027
- Enumerated
- Dec 22, 2006
- Record last updated
- Apr 4, 2024
- Fax
- (209) 529-5398
- Entity
- Type 1 · individual
8 nearest obstetrics & gynecology physician records → All 5,088 in California → Look up another NPI →
Also registered at 1541 Florida Ave Ste 304
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Douglas Phan, M.D.Otolaryngology Physician1013073766
Verify John Charles Pfeffer in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license C400620Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
12.0 times the Medicare Part D claims of the average obstetrics & gynecology physician in 2024
1,972 Medicare Part D claims for 478 beneficiaries, against an average of 165 among the 28,733 providers of this specialty who prescribed in Part D. Brand-name drugs were 16% of claims. 33 claims were for opioids.
Most prescribed
- Estradiol697 claims
- Progesterone95 claims
- Medroxyprogesterone Acetate87 claims
- Premarin79 claims
- Myrbetriq71 claims
- Oxybutynin Chloride Er54 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): 83.6 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: $7,720.13
9 payments; by number, the most common kind was compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program; the largest payer was Intuitive Surgical, Inc. The 21,429 providers of this specialty with any payment received $1,030.61 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.
John Charles Pfeffer among 5,088 obstetrics & gynecology physician records in California
John Charles Pfeffer, M.D. is one of 5,088 obstetrics & gynecology physician records with a practice address in California. 74% 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 5% of them.
- NPI issued2006 · 5% of these records are older, 52% newer
- In a Medicare fileYes · 74% of these records are
- In the CMS Doctors and Clinicians fileNo · 53% of these records are
- Record last updated2024 · 64% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207V00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Obstetrics & Gynecology Physician providers in California
There are 5,088 obstetrics & gynecology physician records in California.
All 5,088 in California → Every provider in Modesto → Obstetrics & Gynecology Physician nationwide →
The 8 obstetrics & gynecology physician records with the nearest ZIP codes
- Rebecca Brock, M.D.Modesto, CA 953501740213875
- Gerald Doersam, MDModesto, CA 953501245525088
- Khary Dorsey, M.D.Modesto, CA 953501992017826
- Christopher Grover, MDModesto, CA 953501033192232
- Margaret Howe, MD/PHDModesto, CA 953501851679021
- Sabrina Hussain, M.D.Modesto, CA 953501629083902
- Lloyd Lee, M.D.Modesto, CA 953501336134303
- Lisa Murphy, MDModesto, CA 953501174506315
Common questions
What is John Charles Pfeffer, M.D.'s NPI number?
John Charles Pfeffer, M.D.'s National Provider Identifier (NPI) is 1851456602, issued on Dec 22, 2006. An NPI identifies a provider in billing; it is not a license.
Where is John Charles Pfeffer, M.D. located?
The NPPES record lists a practice address at 1541 Florida Ave Ste 304, Modesto, CA, 95350. Phone: (209) 522-1027. Providers update this record themselves, so call before visiting.
How can I verify John Charles Pfeffer, M.D.'s license?
NPPES lists California license number C400620, 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 Charles Pfeffer, M.D. prescribe under Medicare Part D?
In 2024, John Charles Pfeffer, M.D. had 1,972 Medicare Part D claims for 478 beneficiaries; the average among obstetrics & gynecology physician prescribers was 165. Part D covers Medicare prescriptions only.
What is John Charles Pfeffer, M.D.'s MIPS final score?
The 2023 MIPS final score is 83.6 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.