Mark S. Horng, MD
Internal Medicine Physician · Los Angeles, CA
Mark S. Horng, MD is an internal medicine physician with a practice address in Los Angeles, California, and NPI 1295739043, issued on Jun 9, 2005. Check the license (California A90098, as entered in NPPES) on the Medical Board of California; the federal record below is the public data PlainDoctor holds for this provider.
- Name
- Mark S. Horng
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License numbers
- A90098 CA
210303 MA
Self-reported in NPPES; status is on the state search - Practice location
- 11301 Wilshire Blvd, Los Angeles, CA 90073
- Phone
- (310) 478-3711
- Enumerated
- Jun 9, 2005
- Record last updated
- Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
- Fax
- (310) 268-4433
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 11301 Wilshire Blvd
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Vanessa AbcedeSocial Worker1306584495
- Maren Abromowitz, FNP-BCFamily Nurse Practitioner1356950919
- Nayiri Adessian, MS, CCC-SLPSpeech-Language Pathologist1326761420
- Farzad AdibStudent in an Organized Health Care Education/Training Program1558745869
Verify Mark S. Horng in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A90098Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Mark S. Horng among 17,696 internal medicine physician records in California
Mark S. Horng, 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 not. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 95% newer
- In a Medicare fileNo · 79% of these records are
- In the CMS Doctors and Clinicians fileNo · 63% of these records are
- Record last updated2007 · 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).
1,423 internal medicine physician records list a practice address in Los Angeles
They are 1,423 of the 69,537 NPPES records with a practice address in Los Angeles, and 17,696 internal medicine physician records in California. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.
All 17,696 in California → Every provider in Los Angeles → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Lisa Altman, M.D.Los Angeles, CA 900731326145095
- Steven Asch, MD MPHLos Angeles, CA 900731487764783
- Joselynn Brazier, M.D.Los Angeles, CA 900731548273188
- Lisa Davis, M.D.Los Angeles, CA 900731376590687
- Peter Glassman, MBBSLos Angeles, CA 900731417976481
- Azadeh Lankarani-Fard, M.D.Los Angeles, CA 900731699871749
- Karl LorenzLos Angeles, CA 900731912017740
- Greg Orshansky, MDLos Angeles, CA 900731568478709
Common questions
What is Mark S. Horng, MD's NPI number?
Mark S. Horng, MD's National Provider Identifier (NPI) is 1295739043, issued on Jun 9, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Mark S. Horng, MD located?
The NPPES record lists a practice address at 11301 Wilshire Blvd, Los Angeles, CA, 90073. Phone: (310) 478-3711. Providers update this record themselves, so call before visiting.
How can I verify Mark S. Horng, MD's license?
NPPES lists California license number A90098, 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. 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.