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Internal Medicine

Alejandro Macias Sustaita, MD

Sees patients in San Antonio, TX · Texas

Summary

Alejandro Macias Sustaita, MD (Internal Medicine) is enrolled with Medicare at 1 practice location in San Antonio, TX. NPI 1447831243. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Alejandro Macias Sustaita, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
5Years since medical school (graduated 2021)
Baylor College Of MedicineMedical school
MaleGender (as listed)
GMG Health Systems Associates PAGroup practice

Quick answers

Where does Alejandro Macias Sustaita see patients?
Medicare's clinician data lists 1 practice location in San Antonio, TX. Call before your visit to confirm the address.
What is Alejandro Macias Sustaita's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Alejandro Macias Sustaita accept Medicare assignment?
Yes. Medicare's clinician data says Alejandro Macias Sustaita accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Alejandro Macias Sustaita?
(210) 509-2603, as listed in official Medicare / NPI Registry data.
What is Alejandro Macias Sustaita's NPI number?
1447831243. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Alejandro Macias Sustaita is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Alejandro Macias Sustaita as a member of this group (CMS data updated 2026-10-02).

  • GMG Health Systems Associates PA117 clinicians in the group

Specialties

Find other Internal Medicine doctors in Texas →

Other internal medicine doctors in San Antonio

Clinicians with the same Medicare primary specialty in San Antonio, TX — not a recommendation.

All internal medicine doctors in San Antonio →

Clinician information

CredentialMD
Medical schoolBaylor College Of Medicine
Graduation year2021
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1447831243
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians