Mariel Muriel Pastrana, MD
Internal Medicine Physician · Walnut Creek, CA
Mariel Muriel Pastrana, MD is an internal medicine physician with a practice address in Walnut Creek, California, and NPI 1538488580, issued on May 28, 2010. Check the license (California A127358, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Mariel Muriel Pastrana
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A127358 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1220 Rossmoor Pkwy, Walnut Creek, CA 94595
- Phone
- (925) 947-3393
- Enumerated
- May 28, 2010
- Record last updated
- Jan 29, 2025
- Medicare enrollment
- Enrolled (PECOS I20140128001945); accepts Medicare assignment
- Medical or professional school
- Ponce School Of Medicine, 2010
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 1220 Rossmoor Pkwy
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Viviane Alfandary, M.D.Internal Medicine Physician1053338095
- Megha AmbatiInternal Medicine Physician1083849111
- Sohrab Amiri, M.D.Internal Medicine Physician1811420243
- Mitchell Applegate, M.D.Hospitalist Physician1093803447
- Anusha Bakshi, M.D.Internal Medicine Physician1346778909
- Christian Balzer, M.D.Internal Medicine Physician1518104892
Verify Mariel Muriel Pastrana in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A127358Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
96% fewer Medicare Part D claims than the average internal medicine physician in 2024
119 Medicare Part D claims for 54 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 10% of claims.
Most prescribed
- Pantoprazole Sodium13 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 one group practice
- Graybill Medical Group IncEscondido, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Mariel Muriel Pastrana among 17,696 internal medicine physician records in California
Mariel Muriel Pastrana, MD is one of 17,696 internal medicine physician records with a practice address in California. 79% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2010, is newer than 63% of them.
- NPI issued2010 · 63% of these records are older, 34% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2010 · median 2004 among the 11,065 with a school on file
- Record last updated2025 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
183 internal medicine physician records list a practice address in Walnut Creek
They are 183 of the 6,170 NPPES records with a practice address in Walnut Creek, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Walnut Creek → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Viviane Alfandary, M.D.Walnut Creek, CA 945951053338095
- Sukhjinder Brah, M.D.Walnut Creek, CA 945951023044559
- Lonnie Bristow, M.D.Walnut Creek, CA 945951871510529
- Smita Chandra, M.D.Walnut Creek, CA 945951811917826
- Han Kyo Chang, M.DWalnut Creek, CA 945951235127150
- Russell Everest, M.D.Walnut Creek, CA 945951528085404
- Kamal Ghei, M.D.Walnut Creek, CA 945951366490120
- Lavinia Herbei, M.D.Walnut Creek, CA 945951508834946
Common questions
What is Mariel Muriel Pastrana, MD's NPI number?
Mariel Muriel Pastrana, MD's National Provider Identifier (NPI) is 1538488580, issued on May 28, 2010. An NPI identifies a provider in billing; it is not a license.
Where is Mariel Muriel Pastrana, MD located?
The NPPES record lists a practice address at 1220 Rossmoor Pkwy, Walnut Creek, CA, 94595. Phone: (925) 947-3393. Providers update this record themselves, so call before visiting.
How can I verify Mariel Muriel Pastrana, MD's license?
NPPES lists California license number A127358, 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 Mariel Muriel Pastrana, MD prescribe under Medicare Part D?
In 2024, Mariel Muriel Pastrana, MD had 119 Medicare Part D claims for 54 beneficiaries; the average among internal medicine physician prescribers was 3,176. 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.