NPI age
7 years
Enumerated 2018-05-31
● Active
Type 1 · Individual
DR. Matthew Alexander Stack, MD
Stack is 1 of 198 internal medicine providers in Houston and 1 of 920 in Texas.
Primary specialty
Internal Medicine
Plus 1 subspecialty
Licensed in
TX, IN
2 states
Status
Active
No deactivations on record
Last NPPES update
2024-05-19
Source: monthly bulk 2026-05
Sole proprietor
No
May be part of a larger org
How this provider compares
Across 920 active internal medicine providers in Texas.
NPI age
7 years
↓ 10 yr below median (17 yr)
State licenses
2 states
Top 83% — 16% of peers are multi-state
Subspecialties
1
In the 35% of peers with subspecialties
NPI lifetime · 2018 → 2026
2018-05Enumerated in NPPES
2018
2026
Where they practice
Practice location
6431 Fannin St # 2.112
Houston, TX 770301501
Mailing address
6431 Fannin St # 2.112
Houston, TX 770301501
Additional practice locations
2 secondary locations on file with NPPES.
Location 2
1008 S Spring Ave
Saint Louis, MO 631102520
Location 3
1120 W Michigan St
Indianapolis, IN 462025209
Specialties
-
Internal Medicine PrimaryAn internist who deals with infectious diseases of all types and in all organ systems. Conditions requiring selective use of antibiotics call for this special skill. This physician often diagnoses and treats AIDS patients and patients...
-
Student in an Organized Health Care Education/Training ProgramAn individual who is enrolled in an organized health care education/training program leading to a degree, certification, registration, and/or licensure to provide health care.
Practice context
Part of a multi-provider practice. 11 other active providers share this practice address in NPPES.
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- Confirm the NPI on NPPES.The CMS registry is the system of record. Open NPPES →
- Check the state license is currently active.State licensing boards publish current status; NPPES does not.
- Confirm payer enrollment if billing.NPI presence does not guarantee active enrollment with Medicare, Medicaid, or commercial payers.