NPI age
20 years
Enumerated 2006-04-18
● Active
Type 1 · Individual
John A Fling, MD
Fling is 1 of 6 allergy & immunology providers in Fort Worth and 1 of 134 in Texas.
Primary specialty
Allergy & Immunology
Plus 1 subspecialty
Licensed in
TX
1 state
Status
Active
No deactivations on record
Last NPPES update
2017-07-05
Source: monthly bulk 2026-05
Sole proprietor
No
May be part of a larger org
How this provider compares
Across 134 active allergy & immunology providers in Texas.
NPI age
20 years
≈ at median (19 yr)
State licenses
1 state
9% of peers hold multiple states
Subspecialties
1
In the 31% of peers with subspecialties
NPI lifetime · 2006 → 2026
2006-04Enumerated in NPPES
2006
2026
Where they practice
Practice location
855 Montgomery St
Fort Worth, TX 761072553
Mailing address
Po Box 99335
Fort Worth, TX 761990335
Specialties
-
Allergy & Immunology PrimaryA physician who specializes in the diagnosis, treatment, and management of allergies.
-
Allergy & ImmunologyAn allergist-immunologist is trained in evaluation, physical and laboratory diagnosis, and management of disorders involving the immune system. Selected examples of such conditions include asthma, anaphylaxis, rhinitis, eczema, and...
Identifiers
| Type | Value | Notes |
|---|---|---|
| 01 (TX) | 114065903 | CSHCN |
| 05 (TX) | 114065902 | |
| 01 (TX) | 847311 | BCBS |
| 05 (TX) | 114065905 | |
| 01 (TX) | 370004852 | RAILROAD MEDICARE PIN |
Practice context
Part of a multi-provider practice. 237 other active providers share this practice address in NPPES.
Provyx · Custom healthcare lists
Need all 134 Allergy & Immunology providers in Texas?
Get the full list as a CSV with verified work emails, direct phones, and LinkedIn URLs.
Request a quote →How to verify this provider
- 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.