NPI age
20 years
Enumerated 2006-05-25
● Active
Type 1 · Individual
DR. Henry Jack Grainger, DO
Grainger is 1 of 1938 internal medicine providers in Houston and 1 of 12343 in Texas.
Primary specialty
Internal Medicine
Plus 2 subspecialties
Licensed in
TX
1 state
Status
Active
No deactivations on record
Last NPPES update
2021-04-12
Source: monthly bulk 2026-05
Sole proprietor
Yes
Solo practice on file
How this provider compares
Across 12343 active internal medicine providers in Texas.
NPI age
20 years
↑ 3 yr above median (17 yr)
State licenses
1 state
12% of peers hold multiple states
Subspecialties
2
In the 33% of peers with subspecialties
NPI lifetime · 2006 → 2026
2006-05Enumerated in NPPES
2006
2026
Where they practice
Practice location
511a W Tidwell Rd
Houston, TX 770914338
Mailing address
511a W Tidwell Rd
Houston, TX 770914338
Specialties
-
Internal Medicine PrimaryA physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer,...
-
Internal MedicineAn internist who specializes in diseases of the heart and blood vessels and manages complex cardiac conditions such as heart attacks and life-threatening, abnormal heartbeat rhythms.
-
Internal MedicineAn internist who has special knowledge of the aging process and special skills in the diagnostic, therapeutic, preventive and rehabilitative aspects of illness in the elderly. This specialist cares for geriatric patients in the...
Identifiers
| Type | Value | Notes |
|---|---|---|
| 01 (TX) | 00R283 | BLUE CROSS BLUE SHIELD |
| 05 (TX) | 115814904 |
Practice context
Part of a multi-provider practice. 4 other active providers share this practice address in NPPES.
Recently enumerated nearby: 6 new internal medicine providers have been added in Houston in the last 180 days.
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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.