Ryan Alistair John Marais, MD
Internal Medicine Physician · Loma Linda, CA
Ryan Alistair John Marais, MD is an internal medicine physician with a practice address in Loma Linda, California, and NPI 1922688282, issued on Apr 12, 2021. Check the license (California A192109, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Ryan Alistair John Marais
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A192109 CA
Self-reported in NPPES; status is on the state search - Practice location
- 11370 Anderson St Ste 3150, Loma Linda, CA 92354
- Phone
- (909) 558-2191
- Enumerated
- Apr 12, 2021
- Record last updated
- Jul 23, 2025
- Medicare enrollment
- Enrolled (PECOS I20250710002353); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 11370 Anderson St Ste 3150
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Gregory Cheek, M.D.Critical Care Medicine (Internal Medicine) Physician1982624003
- Ruth RamonInternal Medicine Physician1063154854
Verify Ryan Alistair John Marais in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A192109Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Bills Medicare through 2 group practices
- Faculty Physicians And Surgeons OF LlusmLoma Linda, CA
- Sac Health SystemSan Bernardino, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Ryan Alistair John Marais among 17,696 internal medicine physician records in California
Ryan Alistair John Marais, 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 2021, is newer than 92% of them.
- NPI issued2021 · 92% of these records are older, 5% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2021 · 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).
212 internal medicine physician records list a practice address in Loma Linda
They are 212 of the 4,863 NPPES records with a practice address in Loma Linda, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Loma Linda → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- David Baylink, M.D.Loma Linda, CA 923541518983113
- David Bee, M.D.Loma Linda, CA 923541720005176
- Adrian Cotton, M.D.Loma Linda, CA 923541639196850
- Debra Craig, M.D.Loma Linda, CA 923541255351151
- Balu Gadhe, M.D.Loma Linda, CA 923541740233808
- Bevan Geslani, M.D.Loma Linda, CA 923541992741862
- Susan Hall, M.D.Loma Linda, CA 923541972523876
- Suchaya Jinamornphongs, M.D.Loma Linda, CA 923541649299876
Common questions
What is Ryan Alistair John Marais, MD's NPI number?
Ryan Alistair John Marais, MD's National Provider Identifier (NPI) is 1922688282, issued on Apr 12, 2021. An NPI identifies a provider in billing; it is not a license.
Where is Ryan Alistair John Marais, MD located?
The NPPES record lists a practice address at 11370 Anderson St Ste 3150, Loma Linda, CA, 92354. Phone: (909) 558-2191. Providers update this record themselves, so call before visiting.
How can I verify Ryan Alistair John Marais, MD's license?
NPPES lists California license number A192109, 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.
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.