Son Nguyen, M.D.
NPI 1114119526 · Internal Medicine Physician · Fairfield, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Son Nguyen, M.D. is a Internal Medicine Physician provider in Fairfield, CA (NPI 1114119526).
Provider details
- NPI number
- 1114119526
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- A100779 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
18 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
1,027 Medicare services, 2024 (ranked within specialty)
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 methodology.
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) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 378 | $122 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 300 | $81 |
| Hospital Discharge Day Management, More Than 30 Minutes99239 | 171 | $121 |
| Initial Hospital Care With Moderate Level of Medical Decision Making, If Using Time, at Least 75 Minutes99223 | 58 | $180 |
| Subsequent Hospital Care With Straightforward Or Low Level of Medical Decision Making, Per Day, If Using Time, at Least 25 Minutes99231 | 48 | $50 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 11 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Losartan Potassium | 26 | 17 |
| Furosemide | 24 | 18 |
| Atorvastatin Calcium | 23 | 16 |
| Hydralazine Hcl | 22 | 11 |
| Metoprolol Succinate | 20 | 13 |
| Clopidogrel Bisulfatebrand: Clopidogrel | 17 | 12 |
| Apixabanbrand: Eliquis |
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-08-10
- Last updated
- 2008-10-18
Frequently asked questions
- What is Son Nguyen's NPI number?
- Son Nguyen's National Provider Identifier (NPI) is 1114119526, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Son Nguyen's specialty?
- Son Nguyen is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Son Nguyen located?
- Son Nguyen's practice location on file with NPPES is 1525 Webster St, Fairfield, CA 94533-4997.
- What is Son Nguyen's phone number?
- The practice phone number listed in the NPPES registry for Son Nguyen is (707) 423-9484.
- Does Son Nguyen accept Medicare?
- Son Nguyen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Son Nguyen's NPI active?
- Yes — Son Nguyen's NPI (1114119526) is active in the NPPES registry as of the last update on 2008-10-18.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.