John Mark Geiss, D.O.
Family Medicine Physician · Santa Ana, CA
John Mark Geiss, D.O. is a family medicine physician with a practice address in Santa Ana, California, and NPI 1053651497, issued on Feb 21, 2013. Check the license (California 20A12647, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- John Mark Geiss
- Credential
- D.O.
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License number
- 20A12647 CA
Self-reported in NPPES; status is on the state search - Practice location
- 5 Hutton Centre Dr Ste 950, Santa Ana, CA 92707
- Phone
- (855) 434-7763
- Enumerated
- Feb 21, 2013
- Record last updated
- Sep 20, 2025
- Fax
- (949) 281-5550
- Medicare enrollment
- Enrolled (PECOS I20250926000369); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 17,133 in California → Look up another NPI →
Also registered at 5 Hutton Centre Dr Ste 950
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Dana Brannigan, MS, PA-CMedical Physician Assistant1467598318
- Gabrielle Carter, RN, PMHNP-BCPsychiatric/Mental Health Nurse Practitioner1245062736
- Jonathan Day, RN, CRNP, PMHNP-BCPsychiatric/Mental Health Nurse Practitioner1306508502
Verify John Mark Geiss in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A12647Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
2.1 times the Medicare Part D claims of the average family medicine physician in 2024
7,562 Medicare Part D claims for 238 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. Brand-name drugs were 17% of claims. 13 claims were for opioids.
Most prescribed
- Atorvastatin Calcium432 claims
- Eliquis376 claims
- Gabapentin323 claims
- Levothyroxine Sodium271 claims
- Metoprolol Tartrate228 claims
- Amlodipine Besylate216 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.
John Mark Geiss among 17,133 family medicine physician records in California
John Mark Geiss, D.O. is one of 17,133 family medicine physician records with a practice address in California. 81% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2013, is newer than 68% of them.
- NPI issued2013 · 68% of these records are older, 29% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 62% of these records are
- Graduated2011 · median 2005 among the 10,652 with a school on file
- Record last updated2025 · 58% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207Q00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
177 family medicine physician records list a practice address in Santa Ana
They are 177 of the 8,904 NPPES records with a practice address in Santa Ana, and 17,133 family medicine physician records in California.
All 17,133 in California → Every provider in Santa Ana → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- Ahmid Dredar, MDSanta Ana, CA 927071174834931
- Chen Ho, MDSanta Ana, CA 927071710029657
- Larissa Luu, MDSanta Ana, CA 927071750940714
- Souhail Toubia, M.D.Santa Ana, CA 927071083962872
- Qiji Toyoda, MDSanta Ana, CA 927071669993994
- Grace Woo, DOSanta Ana, CA 927071720519861
- Diana Alvizo, PACSanta Ana, CA 927061760180970
- Arfa Babaknia, M.D.Fountain Valley, CA 927081205826849
Common questions
What is John Mark Geiss, D.O.'s NPI number?
John Mark Geiss, D.O.'s National Provider Identifier (NPI) is 1053651497, issued on Feb 21, 2013. An NPI identifies a provider in billing; it is not a license.
Where is John Mark Geiss, D.O. located?
The NPPES record lists a practice address at 5 Hutton Centre Dr Ste 950, Santa Ana, CA, 92707. Phone: (855) 434-7763. Providers update this record themselves, so call before visiting.
How can I verify John Mark Geiss, D.O.'s license?
NPPES lists California license number 20A12647, 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 John Mark Geiss, D.O. prescribe under Medicare Part D?
In 2024, John Mark Geiss, D.O. had 7,562 Medicare Part D claims for 238 beneficiaries; the average among family medicine physician prescribers was 3,544. 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.