Santiago Villarreal, M.D.
Nephrology Physician · San Antonio, TX
Santiago Villarreal, M.D. is a nephrology physician with a practice address in San Antonio, Texas, and NPI 1225035199, issued on Jul 7, 2005. Check the license (Texas TX8995, as entered in NPPES) on the Texas Medical Board; the Medicare figures below come from public CMS files.
- Name
- Santiago Villarreal
- Credential
- M.D.
- Primary taxonomy
- Nephrology Physician 207RN0300X
- License number
- TX8995 TX
Self-reported in NPPES; status is on the state search - Practice location
- 4151 Callaghan RD, San Antonio, TX 78228
- Phone
- (210) 647-1195
- Enumerated
- Jul 7, 2005
- Record last updated
- Oct 6, 2023
- Fax
- (210) 521-9473
- Medicare enrollment
- Enrolled (PECOS I20080417000298); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest nephrology physician records → All 1,159 in Texas → Look up another NPI →
Also registered at 4151 Callaghan RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify Santiago Villarreal in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersTexas Medical Board
Search for license TX8995Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
34% fewer Medicare Part D claims than the average nephrology physician in 2024
969 Medicare Part D claims for 119 beneficiaries, against an average of 1,465 among the 10,986 providers of this specialty who prescribed in Part D.
Most prescribed
- Calcium Acetate107 claims
- Sevelamer Carbonate62 claims
- Furosemide60 claims
- Lisinopril55 claims
- Farxiga47 claims
- Carvedilol43 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Industry payments in 2024: $125.37
2 payments; by number, the most common kind was food and beverage; the largest payer was AstraZeneca Pharmaceuticals LP. The 8,230 providers of this specialty with any payment received $3,091.37 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Santiago Villarreal among 1,159 nephrology physician records in Texas
Santiago Villarreal, M.D. is one of 1,159 nephrology physician records with a practice address in Texas. 89% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 85% newer
- In a Medicare fileYes · 89% of these records are
- In the CMS Doctors and Clinicians fileYes · 82% of these records are
- Graduated1977 · median 2001 among the 954 with a school on file
- Record last updated2023 · 47% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RN0300X and a Texas practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Nephrology Physician providers in Texas
There are 1,159 nephrology physician records in Texas.
All 1,159 in Texas → Every provider in San Antonio → Nephrology Physician nationwide →
The 8 nephrology physician records with the nearest ZIP codes
- Fadi Abouzahr, MDSan Antonio, TX 782291982695896
- Wesley Calhoun, M.D.San Antonio, TX 782291174508659
- Larry Davis, M.D.San Antonio, TX 782291386628998
- Susan Diamond, M.D.San Antonio, TX 782291508840125
- Daniel Flood, MDSan Antonio, TX 782291851386536
- Iliana Fred-Miranda, MDSan Antonio, TX 782291851366785
- Steven Gouge, M.D.San Antonio, TX 782291396729927
- Melissa Isbell, MDSan Antonio, TX 782291881660660
Common questions
What is Santiago Villarreal, M.D.'s NPI number?
Santiago Villarreal, M.D.'s National Provider Identifier (NPI) is 1225035199, issued on Jul 7, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Santiago Villarreal, M.D. located?
The NPPES record lists a practice address at 4151 Callaghan RD, San Antonio, TX, 78228. Phone: (210) 647-1195. Providers update this record themselves, so call before visiting.
How can I verify Santiago Villarreal, M.D.'s license?
NPPES lists Texas license number TX8995, as entered by the provider. Search the Texas Medical Board at https://profile.tmb.state.tx.us/Search.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Santiago Villarreal, M.D. prescribe under Medicare Part D?
In 2024, Santiago Villarreal, M.D. had 969 Medicare Part D claims for 119 beneficiaries; the average among nephrology physician prescribers was 1,465. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.