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Dr. Mark Edward Tilyou, M.D.

Legal Medicine in Altoona, PA · enumerated 2005 · practices at Doctors Walk-in Care Inc..

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

National Provider Identifier

1164420717

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark Edward Tilyou
Credential M.D.
Sex Male
Practice address 222 Chestnut Ave, Altoona, PA, 16601
Phone (814) 946-8046
Fax (814) 946-3693
Enumeration date Jul 8, 2005
Last updated in NPPES Jul 13, 2026

Taxonomy & licenses

173000000X Legal Medicine Other Service Providers · License MD023252 (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
001958393 Other - Highmark
1009212900001 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

Where does Mark Tilyou practice?
The practice location on file with NPPES is in Altoona, PA. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Mark Tilyou?
The National Provider Identifier (NPI) for Mark Tilyou is 1164420717, 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 2026-07-13.