Grant Michael Wallenfelsz, MD

Primary specialty

Emergency Medicine PhysicianTaxonomy code 207P00000X

License

T3715 Issued in TX

Practice address

BLDG #50 Farenholt Ave
Agana Heights, GU 96910

Phone

(671) 344-9340

NPI assigned

Apr 1, 2020

Sex

Male

Sole proprietor

No

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

Specialties & licenses 3

Addresses

Medicare fee-for-service enrollment

Enrolled in CA, GU2 enrollments

Eligible to order & refer

• Part B services: Yes
• Medical equipment: Yes
• Home health: Yes
• Power mobility devices: Yes
• Hospice: Yes

Green means eligible to order or refer.

Enrollment records 2

Specialty

Emergency Medicine

Education

Florida State University College of Medicine, 2020

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

Guam Healthcare Development IncorporatedGroup PAC ID 9234351776, 211 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Guam Regional Medical City Hospital, Dededo, GU, CCN 650003

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

Locations

Interoperability endpoints

• Direct secure messaging: gwallenfelsz110675@direct.phhs.org

Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships and National Provider Directory roles.

• Guam Healthcare Development Incorporated

  • Clinic/Center
  • Dededo, GU
  • NPI 1326447939
  Medicare reassignment Care Compare group NPD
• Cep America - California

  • Emergency Medicine Physician
  • Santa Ana, CA
  • NPI 1548667843
  Medicare reassignment NPD
• Cep America - California

  • Emergency Medicine Physician
  • Brawley, CA
  • NPI 1073554002
  NPD
• Cep America-California

  • Emergency Medicine Physician
  • Murrieta, CA
  • NPI 1588552848
  NPD
• NH Guam

  • Military/U.S. Coast Guard Pharmacy
  • Agana Heights, GU
  • NPI 1558214809
  NPD (past)

Hospitals and other facilities this clinician is affiliated with according to Medicare Care Compare.

• Guam Healthcare Development Incorporated

  • General Acute Care Hospital
  • Dededo, GU
  • NPI 1194159525
  Care Compare affiliation

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

{
    "created_epoch": "1585699200000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1759363200000",
    "number": "1194353318",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "MIL",
            "address_1": "PSC 455 BOX 208",
            "city": "FPO",
            "state": "AP",
            "postal_code": "965400003"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "BLDG #50 FARENHOLT AVE",
            "city": "AGANA HEIGHTS",
            "state": "GU",
            "postal_code": "96910",
            "telephone_number": "671-344-9340"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "WALLENFELSZ",
        "first_name": "GRANT",
        "middle_name": "MICHAEL",
        "credential": "MD",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2020-04-01",
        "last_updated": "2025-10-02",
        "certification_date": "2025-10-02",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207P00000X",
            "taxonomy_group": "",
            "desc": "Emergency Medicine",
            "state": "TX",
            "license": "T3715",
            "primary": true
        },
        {
            "code": "207P00000X",
            "taxonomy_group": "",
            "desc": "Emergency Medicine",
            "state": "CA",
            "license": "A187218",
            "primary": false
        },
        {
            "code": "207P00000X",
            "taxonomy_group": "",
            "desc": "Emergency Medicine",
            "state": "GU",
            "license": "M-2480",
            "primary": false
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Gladys Valdez, PA-C
• Stephanie Catherine Vidaurri, LCSW
• Angelie Virgino, BSN,RN
• Eleanor Elizabeth Wade, MD
• Christopher James Walerysiak, PA-C
• Amanda Elizabeth Waller, DO
• Callie Watanabe, MD
• Yuning Weber, DMD
• Marvin Joseph Weniger Jr., MD
• Terry S. West, DDS

• Emergency Medicine Physician in Agana Heights, GU
• Providers in Agana Heights, GU by specialty
• Emergency Medicine Physician in Guam

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Oct 2, 2025; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments; Order and Referring.
• Medicare Care Compare (CMS): clinician profile, group practices, facility affiliations, MIPS scores and star ratings.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.