NPI age
9 years
Enumerated 2017-03-27
● Active
Type 1 · Individual
John Caleb Grenn, M.D.
Grenn is 1 of 141 internal medicine providers in Corpus Christi and 1 of 12343 in Texas.
Primary specialty
Internal Medicine
Plus 1 subspecialty
Licensed in
TX
1 state
Status
Active
No deactivations on record
Last NPPES update
2025-09-09
Source: monthly bulk 2026-05
Sole proprietor
No
May be part of a larger org
How this provider compares
Across 12343 active internal medicine providers in Texas.
NPI age
9 years
↓ 8 yr below median (17 yr)
State licenses
1 state
12% of peers hold multiple states
Subspecialties
1
In the 33% of peers with subspecialties
NPI lifetime · 2017 → 2026
2017-03Enumerated in NPPES
2017
2026
Where they practice
Practice location
3315 S Alameda St
Corpus Christi, TX 784111820
Mailing address
1521 S Staples St Ste 606
Corpus Christi, TX 784043166
Additional practice locations
1 secondary location on file with NPPES.
Location 2
7101 S Padre Island Dr
Corpus Christi, TX 784124913
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,...
-
HospitalistHospitalists are physicians whose primary professional focus is the general medical care of hospitalized patients. Their activities include patient care, teaching, research, and leadership related to Hospital Medicine. The term...
Practice context
Part of a multi-provider practice. 63 other active providers share this practice address in NPPES.
Recently enumerated nearby: 2 new internal medicine providers have been added in Corpus Christi 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.
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