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Dr. John A. Greager II, MD

Surgery Physician in Lombard, IL · enumerated 2006.

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

National Provider Identifier

1427164722

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Registry record

Entity type Individual (Type 1)
Name Dr. John A. Greager II
Credential MD
Sex Male
Practice address 1263 S Highland Ave, Suite 100, Lombard, IL, 60148
Enumeration date Aug 21, 2006
Last updated in NPPES Oct 13, 2007

Taxonomy & licenses

208600000X Surgery Physician Allopathic & Osteopathic Physicians Primary
2086X0206X Surgical Oncology Physician Allopathic & Osteopathic Physicians Secondary
208D00000X General Practice Physician Allopathic & Osteopathic Physicians Secondary
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
3633645526052101 Medicaid IL -

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.

Read the full guide → Validate an NPI →

Frequently asked questions

What specialty is John Greager?
John Greager is registered in NPPES with the primary taxonomy of Surgery Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-10-13.