Gustavo H Day MD PA

Primary specialty

Internal Medicine PhysicianTaxonomy code 207R00000X

Legal business name

GUSTAVO H DAY MD PA

Practice address

7777 Forest LN
Building B, Suite 416
Dallas, TX 75230-2505

Phone

(972) 566-6764

Fax

(972) 566-6968

NPI assigned

Feb 1, 2008

Organization subpart

No

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

Authorized official

Name

Gustavo Horacio Day, MDNPI 1538239173

Title

Owner

Phone

(972) 566-6764

Specialties & licenses 1

Addresses

Other identifiers 1

Medicare fee-for-service enrollment

Enrolled in TX

Enrollment records 1

These CMS records do not include an NPI. They are shown because their name and street address match this provider’s.

CLIA laboratory certificates

Locations

Interoperability endpoints

• FHIR API: https://fhir4.healow.com/fhir/r4/FFGEAD

Practitioners 2

Individual providers connected to this organization through Medicare benefit reassignment, Care Compare group membership or National Provider Directory roles.

• Gustavo Horacio Day, M.D.

  • Internal Medicine Physician
  • Dallas, TX
  • NPI 1538239173
  Medicare reassignment NPD Authorized official
• Melissa Garcia, FNP-C

  • Family Nurse Practitioner
  • Dallas, TX
  • NPI 1609487222
  Medicare reassignment NPD

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

{
    "created_epoch": "1201824000000",
    "enumeration_type": "NPI-2",
    "last_updated_epoch": "1779062400000",
    "number": "1659559664",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "PO BOX 738305",
            "city": "DALLAS",
            "state": "TX",
            "postal_code": "753738305",
            "telephone_number": "972-566-6764",
            "fax_number": "972-566-6968"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "7777 FOREST LN",
            "address_2": "BUILDING B, SUITE 416",
            "city": "DALLAS",
            "state": "TX",
            "postal_code": "752302505",
            "telephone_number": "972-566-6764",
            "fax_number": "972-566-6968"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "organization_name": "GUSTAVO H DAY MD PA",
        "organizational_subpart": "NO",
        "enumeration_date": "2008-02-01",
        "last_updated": "2026-05-18",
        "certification_date": "2026-05-18",
        "status": "A",
        "authorized_official_last_name": "DAY",
        "authorized_official_first_name": "GUSTAVO",
        "authorized_official_middle_name": "HORACIO",
        "authorized_official_title_or_position": "OWNER",
        "authorized_official_telephone_number": "972-566-6764",
        "authorized_official_credential": "MD"
    },
    "taxonomies": [
        {
            "code": "207R00000X",
            "taxonomy_group": "193400000X SINGLE SPECIALTY  GROUP",
            "desc": "Internal Medicine",
            "state": null,
            "license": null,
            "primary": true
        }
    ],
    "identifiers": [
        {
            "code": "05",
            "desc": "MEDICAID",
            "issuer": null,
            "identifier": "P00040AM6",
            "state": "TX"
        }
    ],
    "endpoints": [],
    "other_names": []
}

• Shova Gurung, NP
• Emily Gurwitz
• Kathryn Gurwitz
• Anna Marie Gustafson-Clum, LMSW
• Meghan Patricia Gustafson, RN, CPNP
• Gwenn Carol Guthrie, PT
• James Guthrie, LCDC
• Rebecca Spalding Guthrie, LCSW
• Irina Yuseth Gutierrez Puentes, MD
• Alessandra Amaryllis Gutierrez

• Internal Medicine Physician in Dallas, TX
• Providers in Dallas, TX by specialty
• Internal Medicine Physician in Texas

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on May 18, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments.
• 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.