NPPES file of Aug 9, 2026

Alison S. Breen, MD

Obstetrics & Gynecology Physician · Sacramento, CA

Alison S. Breen, MD is an obstetrics & gynecology physician with a practice address in Sacramento, California, and NPI 1942434238, issued on May 14, 2009. Check the license (California A113675, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1942434238
Name
Alison S. Breen
Credential
MD
Primary taxonomy
Obstetrics & Gynecology Physician 207V00000X
License number
A113675 CA
Self-reported in NPPES; status is on the state search
Practice location
4860 Y St Ste 2500, Sacramento, CA 95817
Phone
(916) 734-6978
Enumerated
May 14, 2009
Record last updated
Aug 24, 2016 (not updated in 10 years: call before relying on the address or phone)
Fax
(916) 734-6666
Medicare enrollment
Enrolled (PECOS I20130729000246); accepts Medicare assignment
Medical or professional school
University Of California, Davis School Of Medicine, 2009
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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Also registered at 4860 Y St Ste 2500

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Nicole Ahmadi, MDObstetrics & Gynecology Physician1639759590
  2. Maryam Ali, MDStudent in an Organized Health Care Education/Training Program1003675430
  3. Sophia Alvarado, MDStudent in an Organized Health Care Education/Training Program1124887641
  4. Magdalena AnchondoStudent in an Organized Health Care Education/Training Program1780318196
  5. Alice Barr, MDGynecologic Oncology Physician1982109286
  6. Sloane Brazina, MDStudent in an Organized Health Care Education/Training Program1912588153

Verify Alison S. Breen in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license A113675
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the California license search

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68% fewer Medicare Part D claims than the average obstetrics & gynecology physician in 2024

52 Medicare Part D claims for 26 beneficiaries, against an average of 165 among the 28,733 providers of this specialty who prescribed in Part D.

  1. Alison Breen52
  2. Specialty average165

Most prescribed

  1. Estradiol27 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

  1. Regents OF The Univ OF CASacramento, CA
  2. Regents OF The University OF CaliforniaElk Grove, CA

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Obstetrics & Gynecology Physician providers in California

There are 5,088 obstetrics & gynecology physician records in California.

Other obstetrics & gynecology physician records in California

  1. Ingrid Aalami, MDSan Jose, CA1952376550
  2. Avisa Abaian- Eagar, M.D.Orange, CA1316057755
  3. Derek Abbassi, MDWalnut Creek, CA1841364155
  4. Ahmed Abdelaziz, MDSanta Maria, CA1790039733
  5. Alireza Abdollah Shamshirsaz, M.D.Palo Alto, CA1881804235
  6. Nicole Abell, DOVentura, CA1811243603
  7. Zachary AbelsonLos Angeles, CA1689237414
  8. Ray Abinader, M.D.Loma Linda, CA1770901548
  9. Tarek Abou El Kheir, M.D.San Bernardino, CA1477521789
  10. Nada Abou-HaibaLos Angeles, CA1134067549

Common questions

What is Alison S. Breen, MD's NPI number?

Alison S. Breen, MD's National Provider Identifier (NPI) is 1942434238, issued on May 14, 2009. An NPI identifies a provider in billing; it is not a license.

Where is Alison S. Breen, MD located?

The NPPES record lists a practice address at 4860 Y St Ste 2500, Sacramento, CA, 95817. Phone: (916) 734-6978. Providers update this record themselves, so call before visiting.

How can I verify Alison S. Breen, MD's license?

NPPES lists California license number A113675, 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 Alison S. Breen, MD prescribe under Medicare Part D?

In 2024, Alison S. Breen, MD had 52 Medicare Part D claims for 26 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.