Allen W. Nan, MD
Obstetrics & Gynecology Physician · Antioch, CA
Allen W. Nan, MD is an obstetrics & gynecology physician with a practice address in Antioch, California, and NPI 1750469326, issued on Nov 1, 2006. Check the license (California G73566, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Allen W. Nan
- Credential
- MD
- Primary taxonomy
- Obstetrics & Gynecology Physician 207V00000X
- License number
- G73566 CA
Self-reported in NPPES; status is on the state search - Practice location
- 5601 Deer Valley RD, Antioch, CA 94531
- Phone
- (925) 813-6500
- Enumerated
- Nov 1, 2006
- Record last updated
- Dec 13, 2021 (not updated in 5 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
8 nearest obstetrics & gynecology physician records → All 5,088 in California → Look up another NPI →
Also registered at 5601 Deer Valley RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Jalal Atmar, MDInternal Medicine Physician1265510846
- Darcy Baird, MDObstetrics & Gynecology Physician1538231337
- Jodi Bryner, PHARM.D.Pharmacist1205035441
- Johanna Burch, MDObstetrics & Gynecology Physician1700413010
- Carol Candiotti, NPNurse Practitioner1346264967
Verify Allen W. Nan in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G73566Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
50% fewer Medicare Part D claims than the average obstetrics & gynecology physician in 2024
82 Medicare Part D claims for 53 beneficiaries, against an average of 165 among the 28,733 providers of this specialty who prescribed in Part D. Brand-name drugs were 30% of claims.
Most prescribed
- Estradiol34 claims
- Estring15 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.
Industry payments in 2024: $16.00
1 payment: food and beverage; the largest payer was Galderma Laboratories, L.P. 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.
Allen W. Nan among 5,088 obstetrics & gynecology physician records in California
Allen W. Nan, MD 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 updated2021 · 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 Antioch → Obstetrics & Gynecology Physician nationwide →
The 8 obstetrics & gynecology physician records with the nearest ZIP codes
- Darcy Baird, MDAntioch, CA 945311538231337
- Johanna Burch, MDAntioch, CA 945311700413010
- Sarah-Bianca Dolisca, M.D.Antioch, CA 945311821529579
- James Ferry, MDAntioch, CA 945311619055704
- Mary Klemm, DOAntioch, CA 945311346328432
- Anahita LatorraAntioch, CA 945311124201223
- Jessica Lennon, MDAntioch, CA 945311093157984
- Cori Pachtman, MDAntioch, CA 945311902984081
Common questions
What is Allen W. Nan, MD's NPI number?
Allen W. Nan, MD's National Provider Identifier (NPI) is 1750469326, issued on Nov 1, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Allen W. Nan, MD located?
The NPPES record lists a practice address at 5601 Deer Valley RD, Antioch, CA, 94531. Phone: (925) 813-6500. Providers update this record themselves, so call before visiting.
How can I verify Allen W. Nan, MD's license?
NPPES lists California license number G73566, 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 Allen W. Nan, MD prescribe under Medicare Part D?
In 2024, Allen W. Nan, MD had 82 Medicare Part D claims for 53 beneficiaries; the average among obstetrics & gynecology physician prescribers was 165. 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.