Mark Joseph Slader, MD
Emergency Medicine Physician · Orange, CA
Mark Joseph Slader, MD is an emergency medicine physician with a practice address in Orange, California, and NPI 1134878440, issued on Mar 22, 2022. Check the license (California A188976, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Mark Joseph Slader
- Credential
- MD
- Primary taxonomy
- Emergency Medicine Physician 207P00000X
- License number
- A188976 CA
Self-reported in NPPES; status is on the state search - Practice location
- 101 The City Dr S, Orange, CA 92868
- Phone
- (714) 456-7890
- Enumerated
- Mar 22, 2022
- Record last updated
- Jun 4, 2025
- Medicare enrollment
- Enrolled (PECOS I20250708000727); may accept Medicare assignment
- Medical or professional school
- University Of California, Irvine, California College Of Medicine, 2022
- Entity
- Type 1 · individual
8 nearest emergency medicine physician records → All 7,751 in California → Look up another NPI →
Also registered at 101 The City Dr S
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Danny Abad, PAPhysician Assistant1477158673
- Edward AbaradoStudent in an Organized Health Care Education/Training Program1912855198
- Nagina Abdiani, DOGeriatric Medicine (Family Medicine) Physician1518543271
- Mariam Abdul-Latif, M.D.Pediatrics Physician1538418884
- Eric AbelloOtolaryngology Physician1922566215
- Brandon Abeyta, MDAnesthesiology Physician1841291804
Verify Mark Joseph Slader in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A188976Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
64% fewer Medicare Part D claims than the average emergency medicine physician in 2024
82 Medicare Part D claims for 58 beneficiaries, against an average of 226 among the 54,106 providers of this specialty who prescribed in Part D.
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
- Avalon Medical Development CorporationAvalon, CA
- Regents OF The University OFOrange, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Mark Joseph Slader among 7,751 emergency medicine physician records in California
Mark Joseph Slader, MD is one of 7,751 emergency 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 2022, is newer than 95% of them.
- NPI issued2022 · 95% of these records are older, 2% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 59% of these records are
- Graduated2022 · median 2011 among the 4,560 with a school on file
- Record last updated2025 · 59% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207P00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
179 emergency medicine physician records list a practice address in Orange
They are 179 of the 13,245 NPPES records with a practice address in Orange, and 7,751 emergency medicine physician records in California.
All 7,751 in California → Every provider in Orange → Emergency Medicine Physician nationwide →
The 8 emergency medicine physician records with the nearest ZIP codes
- Michael Anderson, MDOrange, CA 928681093747750
- Rishi Bhargava, MDOrange, CA 928681407811623
- Jonathan Blair, MDOrange, CA 928681891727954
- Bharath Chakravarthy, MDOrange, CA 928681144259839
- Elizabeth Fiedler, MDOrange, CA 928681578594529
- Jeffrey Hughes, MDOrange, CA 928681871525949
- Michael Menchine, MDOrange, CA 928681912963612
- David Merin, MDOrange, CA 928681811929979
Common questions
What is Mark Joseph Slader, MD's NPI number?
Mark Joseph Slader, MD's National Provider Identifier (NPI) is 1134878440, issued on Mar 22, 2022. An NPI identifies a provider in billing; it is not a license.
Where is Mark Joseph Slader, MD located?
The NPPES record lists a practice address at 101 The City Dr S, Orange, CA, 92868. Phone: (714) 456-7890. Providers update this record themselves, so call before visiting.
How can I verify Mark Joseph Slader, MD's license?
NPPES lists California license number A188976, 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 Joseph Slader, MD prescribe under Medicare Part D?
In 2024, Mark Joseph Slader, MD had 82 Medicare Part D claims for 58 beneficiaries; the average among emergency medicine physician prescribers was 226. 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.