Stephen Nguyen, M.D.
NPI 1265596050 · Internal Medicine Physician · Gaithersburg, MD
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Stephen Nguyen, M.D. is a Internal Medicine Physician provider in Gaithersburg, MD (NPI 1265596050).
Provider details
- NPI number
- 1265596050
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- D0063163 (MD)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
19 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
2,971 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 | 1,250 | $137 |
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 846 | $9 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 589 | $97 |
| Administration of Vaccine90471 | 67 | $22 |
| Routine Electrocardiogram (ecg) Using at Least 12 Leads With Interpretation and Report93000 | 52 | $15 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 143 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 639 | 171 |
| Amlodipine Besylate | 558 | 164 |
| Losartan Potassium | 368 | 104 |
| Pantoprazole Sodium | 290 | 102 |
| Metformin Hcl | 257 | 73 |
| Triamcinolone Acetonide | 232 | 104 |
| Metoprolol Succinate |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$1,904 across 82 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
Registry dates
- Enumerated
- 2006-12-19
- Last updated
- 2025-08-14
- Certified
- 2025-08-14
Frequently asked questions
- What is Stephen Nguyen's NPI number?
- Stephen Nguyen's National Provider Identifier (NPI) is 1265596050, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Stephen Nguyen's specialty?
- Stephen Nguyen is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Stephen Nguyen located?
- Stephen Nguyen's practice location on file with NPPES is 4 Professional Dr Ste 133, Gaithersburg, MD 20879-3426.
- What is Stephen Nguyen's phone number?
- The practice phone number listed in the NPPES registry for Stephen Nguyen is (301) 974-9625.
- Does Stephen Nguyen accept Medicare?
- Stephen Nguyen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Stephen Nguyen's NPI active?
- Yes — Stephen Nguyen's NPI (1265596050) is active in the NPPES registry as of the last update on 2025-08-14.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.