Mary Nguyen, M.D.
NPI 1356339717 · Family Medicine Physician · Castroville, TX
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mary Nguyen, M.D. is a Family Medicine Physician provider in Castroville, TX (NPI 1356339717).
Provider details
- NPI number
- 1356339717
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Female
- Sole proprietor
- Yes
- License
- K5365 (TX)
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
20 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
1,204 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 | 231 | $121 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 144 | $87 |
| Visit Complexity Inherent to Evaluation and Management Associated With Medical Care Services That Serve As the Continuing Focal Point for All Needed Health Care Services And/Or With Medical Care Services That Are Part of Ongoing Care Related to a Patient'SG2211 | 135 | $16 |
| Chronic Care Management Services, First 20 Minutes of Clinical Staff Time Directed By Health Care Professional, Per Calendar Month99490 | 133 | $60 |
| Advance Care Planning, First 30 Minutes99497 | 84 | $78 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 127 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 348 | 98 |
| Rosuvastatin Calcium | 290 | 89 |
| Amlodipine Besylate | 268 | 64 |
| Lisinopril | 237 | 65 |
| Levothyroxine Sodium | 227 | 70 |
| Losartan Potassium | 153 | 50 |
| Gabapentin |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$1,541 across 85 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
- 2005-10-10
- Last updated
- 2013-05-21
Frequently asked questions
- What is Mary Nguyen's NPI number?
- Mary Nguyen's National Provider Identifier (NPI) is 1356339717, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mary Nguyen's specialty?
- Mary Nguyen is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Mary Nguyen located?
- Mary Nguyen's practice location on file with NPPES is 409 Madrid St, Castroville, TX 78009-4527.
- What is Mary Nguyen's phone number?
- The practice phone number listed in the NPPES registry for Mary Nguyen is (830) 538-2254.
- Does Mary Nguyen accept Medicare?
- Mary Nguyen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mary Nguyen's NPI active?
- Yes — Mary Nguyen's NPI (1356339717) is active in the NPPES registry as of the last update on 2013-05-21.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.