Rosa Young Ahn-Horst, MD MPH

Primary specialty

Psychiatry PhysicianTaxonomy code 2084P0800X

License

A201644 Issued in CA

Practice address

401 Quarry Rd
Palo Alto, CA 94304-1419

Phone

(650) 723-5511

NPI assigned

Jul 12, 2019

Sex

Female

Sole proprietor

No

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

Specialties & licenses 2

Addresses

Medicare fee-for-service enrollment

Enrolled in MA

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 1

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Interoperability endpoints

• Direct secure messaging: rahnhorst741334@hisp.ehr.sutterhealth.org

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

{
    "created_epoch": "1562889600000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1785110400000",
    "number": "1649822420",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "401 QUARRY RD",
            "city": "PALO ALTO",
            "state": "CA",
            "postal_code": "943041419"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "401 QUARRY RD",
            "city": "PALO ALTO",
            "state": "CA",
            "postal_code": "943041419",
            "telephone_number": "650-723-5511"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "AHN-HORST",
        "first_name": "ROSA",
        "middle_name": "YOUNG",
        "credential": "MD MPH",
        "sole_proprietor": "NO",
        "sex": "F",
        "enumeration_date": "2019-07-12",
        "last_updated": "2026-07-27",
        "certification_date": "2026-07-27",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "2084P0800X",
            "taxonomy_group": "",
            "desc": "Psychiatry & Neurology, Psychiatry",
            "state": "CA",
            "license": "A201644",
            "primary": true
        },
        {
            "code": "390200000X",
            "taxonomy_group": "",
            "desc": "Student in an Organized Health Care Education/Training Program",
            "state": "CA",
            "license": "A201644",
            "primary": false
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Terence Lee Ahern, MD
• Arlina Ahluwalia, MD
• Iram Nafees Ahmad, MD
• Amina Ahmed, MD
• Syed Uzair Ahmed, MD
• James Ahn, M.D.
• Junsup Justin Ahn, PHARMD
• Namrata Ahuja, M.D.
• Prerna Ahuja, MBBS
• Sergio Aisenberg

• Psychiatry Physician in Palo Alto, CA
• Providers in Palo Alto, CA by specialty
• Psychiatry Physician in California

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jul 27, 2026; 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.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.