Santiago Villarreal, M.D.
NPI 1225035199 · Nephrology Physician · San Antonio, TX
Enrolled with Medicare as Practitioner - Nephrology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Provider details
- NPI number
- 1225035199
- Entity type
- Individual
- Primary specialty
- Nephrology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- TX8995 (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
806 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) |
|---|---|---|
| Subsequent Hospital Care With Straightforward Or Low Level of Medical Decision Making, Per Day, If Using Time, at Least 25 Minutes99231 | 174 | $47 |
| Hemodialysis Procedure With Physician Evaluation90935 | 144 | $67 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 122 | $75 |
| Dialysis Services, 4 Or More Physician Visits Per Month (20 Years Or Older)90960 | 117 | $333 |
| Dialysis Services, 2-3 Physician Visits Per Month (20 Years Or Older)90961 | 107 | $279 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 25 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Calcium Acetate | 107 | 31 |
| Sevelamer Carbonate | 62 | 20 |
| Furosemide | 60 | 21 |
| Lisinopril | 55 | 16 |
| Dapagliflozin Propanediolbrand: Farxiga | 47 | 16 |
| Carvedilol | 43 | 14 |
| Amlodipine Besylate | 38 | 12 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$125 across 2 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
- 2005-07-07
- Last updated
- 2023-10-06
- Certified
- 2023-10-06
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.