Barry F. Zeffren, MD
Listed as an allergist, with 2 practice addresses in Alton and Glen Carbon, Illinois.
Practice locations 2
2 Memorial Dr, Suite 103
Alton, IL 620024 Country Club Executive Park
Glen Carbon, IL 62034
From the records
- Specialty
- Allergist
- Records
- Medicare records: allergy/immunology (October 2026).
- Medicare
- Accepts the Medicare-approved amount as payment in full (Medicare assignment), according to CMS’s file. This applies to Original Medicare; Medicare Advantage plans have their own networks. What assignment means
- Medical school
- Saint Louis University School of Medicine, graduated 1979 (Medicare records)
- Registry record
- Last updated July 2026
- NPI
- 1205908639 (national provider registry)
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From CMS’s Doctors and Clinicians file (October 2026) and the national provider registry, NPPES (October 2026). Listings are free and in alphabetical order; we don’t rate or recommend doctors. How we list doctors