Mark D. Hauptman, M.D.
Internal Medicine Physician · Mission Viejo, CA
Mark D. Hauptman, M.D. is an internal medicine physician with a practice address in Mission Viejo, California, and NPI 1801873427, issued on Dec 23, 2005. Check the license (California G55356, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Mark D. Hauptman
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- G55356 CA
Self-reported in NPPES; status is on the state search - Practice location
- 26991 Crown Valley Pkwy Ste 100, Mission Viejo, CA 92691
- Phone
- (949) 582-5430
- Enumerated
- Dec 23, 2005
- Record last updated
- Sep 4, 2025
- Medicaid ID
- 00G553560 CA
- Medicare enrollment
- Enrolled (PECOS I20091102000631); accepts Medicare assignment
- Medical or professional school
- University Of California, Irvine, California College Of Medicine, 1984
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 26991 Crown Valley Pkwy Ste 100
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Tria Brummond, PA-CPhysician Assistant1952461659
- Michael Burris, FNPFamily Nurse Practitioner1679012041
- Lianne Coulter, PA-CPhysician Assistant1326507062
- Fatemeh Jafari Farshami, M.D.Rheumatology Physician1386049260
- Marco Lopez Vizcarra, M.D.Neurology Physician1467663963
- Camellia Shoapour, MDFamily Medicine Physician1154883940
Verify Mark D. Hauptman in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G55356Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
84% fewer Medicare Part D claims than the average internal medicine physician in 2024
500 Medicare Part D claims for 77 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.
Most prescribed
- Atorvastatin Calcium51 claims
- Ramipril46 claims
- Amlodipine Besylate28 claims
- Alendronate Sodium27 claims
- Losartan Potassium25 claims
- Tamsulosin Hcl22 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
- Centers For Family Medicine GPMission Viejo, CA
- Healthcare Partners Affiliates Medical GroupMission Viejo, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Mark D. Hauptman among 17,696 internal medicine physician records in California
Mark D. Hauptman, M.D. 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 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 95% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated1984 · 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).
58 internal medicine physician records list a practice address in Mission Viejo
They are 58 of the 2,156 NPPES records with a practice address in Mission Viejo, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Mission Viejo → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Bahman Badie, M.D.Mission Viejo, CA 926911396721916
- Sherif El Sokkary, M.D.Mission Viejo, CA 926911710964432
- Dennis Haghighat, M.D.Mission Viejo, CA 926911568449171
- Raymond Kwa, M.D.Mission Viejo, CA 926911609853092
- Murray Margolis, M.D.Mission Viejo, CA 926911457338857
- Vy Nguyen, M.D.Mission Viejo, CA 926911881671154
- Nader Noorian, M.D.Mission Viejo, CA 926911861479057
- Donald Pratt, M.D.Mission Viejo, CA 926911437136660
Common questions
What is Mark D. Hauptman, M.D.'s NPI number?
Mark D. Hauptman, M.D.'s National Provider Identifier (NPI) is 1801873427, issued on Dec 23, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Mark D. Hauptman, M.D. located?
The NPPES record lists a practice address at 26991 Crown Valley Pkwy Ste 100, Mission Viejo, CA, 92691. Phone: (949) 582-5430. Providers update this record themselves, so call before visiting.
How can I verify Mark D. Hauptman, M.D.'s license?
NPPES lists California license number G55356, 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 Mark D. Hauptman, M.D. prescribe under Medicare Part D?
In 2024, Mark D. Hauptman, M.D. had 500 Medicare Part D claims for 77 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.