Christopher A. O'Brien, FNP

Primary specialty

Registered NurseTaxonomy code 163W00000X

License

RN155670 Issued in AZ

Practice address

123 S Beaver St
Flagstaff, AZ 86001-5601

Phone

(123) 123-1234

NPI assigned

Oct 14, 2026

Last updated

Oct 14, 2026By the provider in NPPES

Sex

Male

Sole proprietor

Yes

Registry information is reported by the provider to CMS and is not verified. About this source

Specialties & licenses 1

Addresses

Medicare fee-for-service enrollment

Not listed in the public Medicare enrollment file

Medicare enrollment (NPD)

Not enrolled

The complete NPPES record for this NPI in the NPI Registry API format.

{
    "created_epoch": "1791936000000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1791936000000",
    "number": "1740186071",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "78 E CEDAR AVE",
            "city": "FLAGSTAFF",
            "state": "AZ",
            "postal_code": "860011446",
            "telephone_number": "520-730-8653"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "123 S BEAVER ST",
            "city": "FLAGSTAFF",
            "state": "AZ",
            "postal_code": "860015601",
            "telephone_number": "123-123-1234"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "O'BRIEN",
        "first_name": "CHRISTOPHER",
        "middle_name": "A.",
        "name_prefix": "Mr.",
        "credential": "FNP",
        "sole_proprietor": "YES",
        "sex": "M",
        "enumeration_date": "2026-10-14",
        "last_updated": "2026-10-14",
        "certification_date": "2026-10-14",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "163W00000X",
            "taxonomy_group": "",
            "desc": "Registered Nurse",
            "state": "AZ",
            "license": "RN155670",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Nancy Ann Novak, RN
• Katherine Maples Novotny, RN
• NP Fromhome, LLC
• Hannah Ruth Nunez, LPC
• Mallory Jo Nyenhuis, D.D.S.
• Sherry O'Brien, NURSE PRACTITIONER
• Claire O'Connell
• Rachel Michelle O'Connor, D.P.M.
• Kelly Marie O'Donnell, LCSW
• Meghan O'Donnell, MD

• Registered Nurse in Flagstaff, AZ
• Providers in Flagstaff, AZ by specialty
• Registered Nurse in Arizona

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Oct 14, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.