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Dr. John J Messmer, MD

Family Medicine Physician in Palmyra, PA · enumerated 2006 · practices at The Milton S Hershey Medical Center Physicians Group.

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

National Provider Identifier

1669437414

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Registry record

Entity type Individual (Type 1)
Name Dr. John J Messmer
Credential MD
Sex Male
Practice address 941 Park Dr, Palmyra, PA, 17078
Phone (800) 233-4082
Enumeration date Apr 17, 2006
Last updated in NPPES Nov 16, 2009

Taxonomy & licenses

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License MD020821E (PA) 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
0010533300007 Medicaid PA -

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

What is the NPI number for John Messmer?
The National Provider Identifier (NPI) for John Messmer is 1669437414, a Type 1 (individual) record in the CMS NPPES registry.
Where does John Messmer practice?
The practice location on file with NPPES is in Palmyra, PA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-11-16.