Douglas Nguyen, MD
NPI 1184880114 · Gastroenterology Physician · Mission Viejo, CA
Enrolled with Medicare as Practitioner - Gastroenterology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Douglas Nguyen, MD is a Gastroenterology Physician provider in Mission Viejo, CA (NPI 1184880114).
Provider details
- NPI number
- 1184880114
- Entity type
- Individual
- Primary specialty
- Gastroenterology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- A113814 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
17 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
866 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 345 | $138 |
| Biopsy of Esophagus, Stomach, And/Or Upper Small Bowel Using a Flexible Endoscope43239 | 124 | $75 |
| New Patient Office Or Other Outpatient Visit With Moderate Level of Medical Decision Making, If Using Time, 45 Minutes Or More99204 | 122 | $178 |
| Removal of Polyps Or Growths of Large Bowel Using an Endoscope With Mechanical Snare45385 | 102 | $221 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 34 | $99 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 34 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Pantoprazole Sodium | 295 | 124 |
| Sodium, Potassium,mag Sulfatesbrand: Sod Sulf-Potass Sulf-Mag Sulf | 120 | 117 |
| Lactulose | 114 | 54 |
| Omeprazole | 89 | 36 |
| Colestipol Hcl | 73 | 24 |
| Linaclotidebrand: Linzess | 65 | 28 |
| Mirtazapine | 56 | 21 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$486,244 across 654 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 11234 Anderson St # Mc-1516Loma Linda, CA 92354-2804Phone: (909) 558-4905Fax: (909) 558-4028
Registry dates
- Enumerated
- 2008-07-30
- Last updated
- 2022-05-12
- Certified
- 2022-05-12
Frequently asked questions
- What is Douglas Nguyen's NPI number?
- Douglas Nguyen's National Provider Identifier (NPI) is 1184880114, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Douglas Nguyen's specialty?
- Douglas Nguyen is listed in the NPPES registry with a primary specialty of Gastroenterology Physician (Allopathic & Osteopathic Physicians).
- Where is Douglas Nguyen located?
- Douglas Nguyen's practice location on file with NPPES is 27799 Medical Center Rd Ste 310, Mission Viejo, CA 92691-6400.
- What is Douglas Nguyen's phone number?
- The practice phone number listed in the NPPES registry for Douglas Nguyen is (949) 364-5090.
- Does Douglas Nguyen accept Medicare?
- Douglas Nguyen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Douglas Nguyen's NPI active?
- Yes — Douglas Nguyen's NPI (1184880114) is active in the NPPES registry as of the last update on 2022-05-12.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.