Individual Healthcare Provider
Douglas Thomas Johnston, DO
Provider's NPPES record last updated: August 16, 2022
Overview
- Entity Type
- Individual Healthcare Provider
- NPI
- 1124048079
- Primary Specialty
- Allergy & Immunology
- Practice Location
- Greenville, South Carolina
- Sole Proprietor
- No
Federal Screening
NPISignal checked this NPI against federal exclusion sources. Results below are based on the NPI number itself — an identifier match, not a name match.
List of Excluded Individuals/Entities (LEIE)
HHS Office of Inspector General
No potential match was identified in NPISignal's indexed List of Excluded Individuals/Entities (LEIE) records as of 2026-09-10.
- Source data
- September 10, 2026
- Records indexed
- 84,001
- Screened
- Sep 18, 2026, 8:03 AM UTC
This reflects only the records NPISignal currently holds and the identity information supplied. It is not a verification of eligibility, licensure, or compliance. Verify decisions that matter against the authoritative source.
SAM.gov Exclusions
U.S. General Services Administration
SAM.gov Exclusions was not checked.
SAM.gov screening is not configured on this deployment. No SAM check has been performed.
- Screened
- Not checked
This is an NPI-based check only. NPISignal does not publish name-based exclusion matches on a provider profile. A shared or similar name is a lead that requires human review, not an identification, and this page is not the place to make one. Run a name-based screening below to see potential matches with the reasons for each.
This reflects only the records NPISignal currently holds and the identity information supplied. It is not a verification of eligibility, licensure, or compliance. Verify decisions that matter against the authoritative source.
Searches OIG LEIE and SAM.gov by name and reviews every potential match.
Specialties & Taxonomies
- Primary
Allergy & Immunology
Allopathic & Osteopathic Physicians
An 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 adverse reactions to drugs, foods, and insect stings as well as immune deficiency diseases (both acquired and congenital), defects in host defense, and problems related to autoimmune disease, organ transplantation, or malignancies of the immune system.
Taxonomy code 207K00000X
Provider-Reported License Information
- Allergy & Immunology (South Carolina)
- 967
- Allergy & Immunology (North Carolina)
- 2011-01906
- Allergy & Immunology (Alabama)
- DO840
Practice Locations
Practice Location
200 Patewood Dr Ste A140
Greenville, South Carolina 29615-3585
Phone: (864) 454-5125
Additional Practice Location
10310 Mallard Creek Rd Ste 101a
Charlotte, North Carolina 28262-4563
Phone: (704) 341-9600
Additional Practice Location
2600 E 7th St Unit A
Charlotte, North Carolina 28204-4398
Phone: (704) 372-7900
Additional Practice Location
8045 Providence Rd
Suite 300
Charlotte, North Carolina 28277-8915
Phone: (704) 341-9600
Fax: (704) 341-9996
Record Information
- Enumeration Date
- July 20, 2006
- Provider's NPPES Record Last Updated
- August 16, 2022
- Certification Date
- August 16, 2022
- NPISignal NPPES Dataset
- August 2026
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