Sze Hoay Ding, M.D.
Internal Medicine Physician · San Marcos, CA
Sze Hoay Ding, M.D. is an internal medicine physician with a practice address in San Marcos, California, and NPI 1023239035, issued on May 1, 2007. Check the license (California C141004, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Sze Hoay Ding
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- C141004 CA
Self-reported in NPPES; status is on the state search - Practice location
- 400 Craven RD, San Marcos, CA 92078
- Phone
- (619) 318-7476
- Enumerated
- May 1, 2007
- Record last updated
- Mar 7, 2023
- Medicare enrollment
- Enrolled (PECOS I20161020001523); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 400 Craven RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Tracy Abrams, R.N.Registered Nurse1073991261
- Eric Adiarte, M.D.Obstetrics & Gynecology Physician1902038284
- Shreya Aiyar, MDPediatrics Physician1922685981
- Najlaa Al-Jibouri, PHARM DPharmacist1447438965
- Jennifer Alexander, RCP, RRTPulmonary Function Technologist Certified Respiratory Therapist1023596442
- Marisa Alunni, M.D.Obstetrics & Gynecology Physician1710298476
Verify Sze Hoay Ding in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license C141004Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
98% more Medicare Part D claims than the average internal medicine physician in 2024
6,303 Medicare Part D claims for 624 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 8% of claims. 290 claims were for opioids.
Most prescribed
- Atorvastatin Calcium380 claims
- Levothyroxine Sodium357 claims
- Amlodipine Besylate328 claims
- Rosuvastatin Calcium320 claims
- Losartan Potassium256 claims
- Lisinopril240 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.
Industry payments in 2024: $112.55
1 payment: food and beverage; the largest payer was ConvaTec Inc. The 50,334 providers of this specialty with any payment received $1,303.06 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- Southern California Permanente Medical GroupSan Marcos, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Sze Hoay Ding among 17,696 internal medicine physician records in California
Sze Hoay Ding, 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 2007, is newer than 44% of them.
- NPI issued2007 · 44% of these records are older, 44% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2000 · median 2004 among the 11,065 with a school on file
- Record last updated2023 · 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).
Internal Medicine Physician providers in California
There are 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in San Marcos → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Meenu Bawa, M.DSan Marcos, CA 920781154598571
- Justin Charles, MDSan Marcos, CA 920781811552771
- Lauren Clarine, D.O.San Marcos, CA 920781669738928
- Joseph Czvik, MDSan Marcos, CA 920781528084340
- Kathryn Germeraad, DOSan Marcos, CA 920781649830498
- Francisco Marquez, M.D.San Marcos, CA 920781316190747
- Minh Nguyen, M.D.San Marcos, CA 920781154403640
- Tyler Sprague, D.O.San Marcos, CA 920781881077428
Common questions
What is Sze Hoay Ding, M.D.'s NPI number?
Sze Hoay Ding, M.D.'s National Provider Identifier (NPI) is 1023239035, issued on May 1, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Sze Hoay Ding, M.D. located?
The NPPES record lists a practice address at 400 Craven RD, San Marcos, CA, 92078. Phone: (619) 318-7476. Providers update this record themselves, so call before visiting.
How can I verify Sze Hoay Ding, M.D.'s license?
NPPES lists California license number C141004, 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 Sze Hoay Ding, M.D. prescribe under Medicare Part D?
In 2024, Sze Hoay Ding, M.D. had 6,303 Medicare Part D claims for 624 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.