J. Xavier Castillo, MD
Internal Medicine Physician · Houston, TX
J. Xavier Castillo, MD is an internal medicine physician with a practice address in Houston, Texas, and NPI 1720013501, issued on Jul 11, 2006. Check the license (Texas K4016, as entered in NPPES) on the Texas Medical Board; the Medicare figures below come from public CMS files.
- Name
- J. Xavier Castillo
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- K4016 TX
Self-reported in NPPES; status is on the state search - Practice location
- 1111 Augusta Dr, Houston, TX 77057
- Phone
- (713) 442-2400
- Enumerated
- Jul 11, 2006
- Record last updated
- Jun 5, 2021 (not updated in 5 years: call before relying on the address or phone)
- Medicaid IDs
- 042829401 TX
042829403 TX
042829404 TX - Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 9,175 in Texas → Look up another NPI →
Also registered at 1111 Augusta Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Jamise Crooms, M.D.Internal Medicine Physician1104269810
- Enrique Cuevo, MDFamily Medicine Physician1770514721
- Robert Dillon, M.D.Urology Physician1679541577
- Thomas Doneker, MDInternal Medicine Physician1902909104
Verify J. Xavier Castillo in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersTexas Medical Board
Search for license K4016Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
74% fewer Medicare Part D claims than the average internal medicine physician in 2024
829 Medicare Part D claims for 235 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.
Most prescribed
- Atorvastatin Calcium96 claims
- Lisinopril57 claims
- Amlodipine Besylate30 claims
- Tamsulosin Hcl26 claims
- Alendronate Sodium24 claims
- Metformin Hcl24 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.
J. Xavier Castillo among 9,175 internal medicine physician records in Texas
J. Xavier Castillo, MD is one of 9,175 internal medicine physician records with a practice address in Texas. 82% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 9% of them.
- NPI issued2006 · 9% of these records are older, 59% newer
- In a Medicare fileYes · 82% of these records are
- In the CMS Doctors and Clinicians fileNo · 66% of these records are
- Record last updated2021 · 49% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Texas practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
1,488 internal medicine physician records list a practice address in Houston
They are 1,488 of the 61,221 NPPES records with a practice address in Houston, and 9,175 internal medicine physician records in Texas.
All 9,175 in Texas → Every provider in Houston → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Chia Arif, M.D.Houston, TX 770571205455581
- Jamise Crooms, M.D.Houston, TX 770571104269810
- Thomas Doneker, MDHouston, TX 770571902909104
- George Katei, M.D.Houston, TX 770571992701346
- Angel Rodriguez, M.D.Houston, TX 770571609804046
- Kathleen Ryan, MDHouston, TX 770571164518346
- Patricia Salvato, M.D.Houston, TX 770571043218845
- Maya Sarihan, MDHouston, TX 770571588307771
Common questions
What is J. Xavier Castillo, MD's NPI number?
J. Xavier Castillo, MD's National Provider Identifier (NPI) is 1720013501, issued on Jul 11, 2006. An NPI identifies a provider in billing; it is not a license.
Where is J. Xavier Castillo, MD located?
The NPPES record lists a practice address at 1111 Augusta Dr, Houston, TX, 77057. Phone: (713) 442-2400. Providers update this record themselves, so call before visiting.
How can I verify J. Xavier Castillo, MD's license?
NPPES lists Texas license number K4016, 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 J. Xavier Castillo, MD prescribe under Medicare Part D?
In 2024, J. Xavier Castillo, MD had 829 Medicare Part D claims for 235 beneficiaries; the average among internal medicine physician prescribers was 3,176. 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.