Douglas Long Nguyen, MD
Gastroenterology Physician · Mission Viejo, CA
Douglas Long Nguyen, MD is a gastroenterology physician with a practice address in Mission Viejo, California, and NPI 1184880114, issued on Jul 30, 2008. Check the license (California A113814, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Douglas Long Nguyen
- Credential
- MD
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License number
- A113814 CA
Self-reported in NPPES; status is on the state search - Practice location
- 27799 Medical Center RD Ste 310, Mission Viejo, CA 92691
- Phone
- (949) 364-5090
- Enumerated
- Jul 30, 2008
- Record last updated
- May 12, 2022
- Medicaid ID
- ENROLLED MN
- Medicare enrollment
- Enrolled (PECOS I20121114000034); accepts Medicare assignment
- Medical or professional school
- Cincinnati College Of Medicine And Surgery, 2008
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 2,140 in California → Look up another NPI →
Also registered at 27799 Medical Center RD Ste 310
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Daniel Kim, MDGastroenterology Physician1548648868
- Lien Nguyen, NPNurse Practitioner1508906033
Verify Douglas Long Nguyen in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A113814Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
2.0 times the Medicare Part D claims of the average gastroenterology physician in 2024
1,654 Medicare Part D claims for 466 beneficiaries, against an average of 811 among the 16,445 providers of this specialty who prescribed in Part D. Brand-name drugs were 26% of claims.
Most prescribed
- Pantoprazole Sodium295 claims
- Sod Sulf-Potass Sulf-Mag Sulf120 claims
- Lactulose114 claims
- Omeprazole89 claims
- Colestipol Hcl73 claims
- Linzess65 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: $486,243.72
654 payments; by number, the most common kind was food and beverage; the largest payer was Abbvie Inc. The 13,350 providers of this specialty with any payment received $5,015.95 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
- Providence Medical FoundationFullerton, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Douglas Long Nguyen among 2,140 gastroenterology physician records in California
Douglas Long Nguyen, MD is one of 2,140 gastroenterology physician records with a practice address in California. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2008, is newer than 63% of them.
- NPI issued2008 · 63% of these records are older, 31% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 72% of these records are
- Graduated2008 · median 2002 among the 1,538 with a school on file
- Record last updated2022 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RG0100X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gastroenterology Physician providers in California
There are 2,140 gastroenterology physician records in California.
All 2,140 in California → Every provider in Mission Viejo → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Ronald Adamany, M.D.Mission Viejo, CA 926911992780688
- Wanjun Bae, M.D.Mission Viejo, CA 926911457433906
- Edward Block, M.D.Mission Viejo, CA 926911811973860
- Elmer Chang, M.D.Mission Viejo, CA 926911912083353
- Om Chaurasia, MDMission Viejo, CA 926911528136702
- Jack Feng, M.D.Mission Viejo, CA 926911710964481
- Shahram Javaheri, M.D.Mission Viejo, CA 926911497861439
- Jae Lee, M.D.Mission Viejo, CA 926911194702563
Common questions
What is Douglas Long Nguyen, MD's NPI number?
Douglas Long Nguyen, MD's National Provider Identifier (NPI) is 1184880114, issued on Jul 30, 2008. An NPI identifies a provider in billing; it is not a license.
Where is Douglas Long Nguyen, MD located?
The NPPES record lists a practice address at 27799 Medical Center RD Ste 310, Mission Viejo, CA, 92691. Phone: (949) 364-5090. Providers update this record themselves, so call before visiting.
How can I verify Douglas Long Nguyen, MD's license?
NPPES lists California license number A113814, 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 Douglas Long Nguyen, MD prescribe under Medicare Part D?
In 2024, Douglas Long Nguyen, MD had 1,654 Medicare Part D claims for 466 beneficiaries; the average among gastroenterology physician prescribers was 811. 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.