Kerstyn A. O'Brien, PA-C
Medical Physician Assistant · Fresno, CA
Kerstyn A. O'Brien, PA-C is a medical physician assistant with a practice address in Fresno, California, and NPI 1972179992, issued on Jun 1, 2021. Check the license (California 59940, as entered in NPPES) with the California board that licenses this profession; the Medicare figures below come from public CMS files.
- Name
- Kerstyn A. O'Brien
- Credential
- PA-C
- Primary taxonomy
- Medical Physician Assistant 363AM0700X
- License number
- 59940 CA
Self-reported in NPPES; status is on the state search - Practice location
- 2335 E Kashian LN Ste 260, Fresno, CA 93701
- Phone
- (559) 256-5130
- Enumerated
- Jun 1, 2021
- Record last updated
- Aug 26, 2021 (not updated in 5 years: call before relying on the address or phone)
- Fax
- (559) 485-4504
- Medicare enrollment
- Enrolled (PECOS I20211014000732); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest medical physician assistant records → All 3,376 in California → Look up another NPI →
Also registered at 2335 E Kashian LN Ste 260
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Waqas Aslam, M.DCritical Care Medicine (Internal Medicine) Physician1841509320
- Vijay Balasubramanian, MDPulmonary Disease Physician1548289093
- Sonja JoplinPhysician Assistant1780263202
- Coralee Koning, PA-CMedical Physician Assistant1992793525
- Robin McBride, NP-CNurse Practitioner1912662735
- Daya Upadhyay, M.D.Pulmonary Disease Physician1710029798
Verify Kerstyn A. O'Brien in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich California board licenses this profession
Search for license 59940Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
90% fewer Medicare Part D claims than the average medical physician assistant in 2024
118 Medicare Part D claims for 36 beneficiaries, against an average of 1,148 among the 23,801 providers of this specialty who prescribed in Part D. Brand-name drugs were 54% of claims.
Most prescribed
- Advair Hfa15 claims
- Trelegy Ellipta15 claims
- Albuterol Sulfate Hfa13 claims
- Breyna11 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): 85 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: $482.85
12 payments; by number, the most common kind was food and beverage; the largest payer was Pulmonx Corporation. The 16,165 providers of this specialty with any payment received $1,055.00 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 one group practice
- Faculty Physicians And Surgeons OF LlusmLoma Linda, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Kerstyn A. O'Brien among 3,376 medical physician assistant records in California
Kerstyn A. O'Brien, PA-C is one of 3,376 medical physician assistant records with a practice address in California. 69% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2021, is newer than 79% of them.
- NPI issued2021 · 79% of these records are older, 18% newer
- In a Medicare fileYes · 69% of these records are
- In the CMS Doctors and Clinicians fileYes · 40% of these records are
- Graduated2021 · median 2012 among the 1,347 with a school on file
- Record last updated2021 · 54% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 363AM0700X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Medical Physician Assistant providers in California
There are 3,376 medical physician assistant records in California.
All 3,376 in California → Every provider in Fresno → Medical Physician Assistant nationwide →
The 8 medical physician assistant records with the nearest ZIP codes
- Theresa DwyerFresno, CA 937011982187100
- Linda Gutierrez, PAFresno, CA 937011437136348
- Coralee Koning, PA-CFresno, CA 937011992793525
- Donna Mau, P.A.-CFresno, CA 937011669457552
- Sheila Mayo, PA-CFresno, CA 937011366532145
- Stephanie Mercado, PA-CFresno, CA 937011508909888
- Bounmy Pinyasone, PA-C, MPASFresno, CA 937011750505061
- Sylvia Sanchez, PA-CFresno, CA 937011437220530
Common questions
What is Kerstyn A. O'Brien, PA-C's NPI number?
Kerstyn A. O'Brien, PA-C's National Provider Identifier (NPI) is 1972179992, issued on Jun 1, 2021. An NPI identifies a provider in billing; it is not a license.
Where is Kerstyn A. O'Brien, PA-C located?
The NPPES record lists a practice address at 2335 E Kashian LN Ste 260, Fresno, CA, 93701. Phone: (559) 256-5130. Providers update this record themselves, so call before visiting.
How can I verify Kerstyn A. O'Brien, PA-C's license?
NPPES lists California license number 59940, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity only.
How much does Kerstyn A. O'Brien, PA-C prescribe under Medicare Part D?
In 2024, Kerstyn A. O'Brien, PA-C had 118 Medicare Part D claims for 36 beneficiaries; the average among medical physician assistant prescribers was 1,148. Part D covers Medicare prescriptions only.
What is Kerstyn A. O'Brien, PA-C's MIPS final score?
The 2023 MIPS final score is 85 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.