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Dr. Michael Harris Callahan, M.D.

Otolaryngic Allergy Physician in Gainesville, GA · enumerated 2007.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1063564243

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Registry record

Entity type Individual (Type 1)
Name Dr. Michael Harris Callahan
Credential M.D.
Sex Male
Practice address 584 Lanier Park Dr, Gainesville, GA, 30501
Phone (770) 534-5208
Fax (770) 534-8512
Enumeration date Jan 17, 2007
Last updated in NPPES Oct 4, 2011

Taxonomy & licenses

207YX0602X Otolaryngic Allergy Physician Allopathic & Osteopathic Physicians · License 045050 (GA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
00906386A Medicaid GA -

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Where does Michael Callahan practice?
The practice location on file with NPPES is in Gainesville, GA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Michael Callahan?
The National Provider Identifier (NPI) for Michael Callahan is 1063564243, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-10-04.