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Ms. Mary Elizabeth Massieu, DNP, FNP -C

Family Nurse Practitioner in Dewey, AZ · enumerated 2014 · practices at Northern Arizona Pharmacy LLC.

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

National Provider Identifier

1144644287

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Registry record

Entity type Individual (Type 1)
Name Ms. Mary Elizabeth Massieu
Credential DNP, FNP -C
Sex Female
Practice address 12075 E State Route 69, Dewey, AZ, 86327
Phone (928) 777-9600
Fax (602) 218-4443
Enumeration date Feb 10, 2014
Last updated in NPPES Oct 19, 2024

Taxonomy & licenses

363LF0000X Family Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License ARNP2936392 (FL) Secondary
363LF0000X Family Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 226377 (AZ) Primary
DNP · Doctor of Nursing Practice: A clinical doctorate for advanced practice nurses. About the DNP credential

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

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.
What specialty is Mary Massieu?
Mary Massieu is registered in NPPES with the primary taxonomy of Family Nurse Practitioner. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2024-10-19.