Allison Alden Merz-Herrala, MD

Primary specialty

Complex Family Planning PhysicianTaxonomy code 207VC0300X

License

A185547 Issued in CA

Practice address

300 Pasteur Dr
Stanford, CA 94305-2200

Phone

(650) 723-4000

NPI assigned

Apr 4, 2020

Last updated

Sep 14, 2026By the provider in NPPES

Sex

Female

Sole proprietor

Yes

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 CA

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

Specialty

Obstetrics/Gynecology

Education

Harvard Medical School, 2020

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

University of California SFGH Medical GroupGroup PAC ID 5496668410, 566 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Zuckerberg San Francisco General Hosp & Trauma Ctr Hospital, San Francisco, CA, CCN 050228

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

Locations

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

• University of California SFGH Medical Group

  dba UCSF SFGH Medical Group Dept of Anesthesia

  • Anesthesiology Physician
  • San Francisco, CA
  • NPI 1366417420
  Medicare reassignment Care Compare group NPD
• City & County of San Francisco

  dba San Francisco Public Health Laboratory

  • Clinical Medical Laboratory
  • San Francisco, CA
  • NPI 1982737524
  Medicare reassignment NPD
• Planned Parenthood Shasta Diablo Inc

  • Community Health Clinic/Center
  • Concord, CA
  • NPI 1982763090
  Medicare reassignment NPD
• City & County of San Francisco

  dba CCSF DPH Multi - Practice Medical Group

  • Community Health/Public Health Clinical Nurse Specialist
  • San Francisco, CA
  • NPI 1609041060
  NPD
• City and County of San Francisco

  dba DSAAM OTOP Methadone Maintenance

  • Methadone Clinic
  • San Francisco, CA
  • NPI 1578787925
  NPD
• Planned Parenthood Shasta Diablo Inc

  dba Planned Parenthood Northern California

  • Clinical Medical Laboratory
  • San Rafael, CA
  • NPI 1750435244
  NPD
• University of California SFGH Medical Group

  dba UCSF SFGH Medical Group Division of Vascular Surgery

  • Vascular Surgery Physician
  • San Francisco, CA
  • NPI 1033913959
  NPD
• University of California SFGH Medical Group

  dba UCSF SFGH Medical Group Dept of OBGYN

  • Obstetrics & Gynecology Physician
  • San Francisco, CA
  • NPI 1407821523
  NPD

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

• City & County of San Francisco

  dba Zuckerberg San Francisco General Hospital and Trauma Center- Acute

  • General Acute Care Hospital
  • San Francisco, CA
  • NPI 1083648810
  Care Compare affiliation
• City & County of San Francisco

  dba Zuckerberg San Francisco General Hospital and Trauma Center - Acute

  • General Acute Care Hospital
  • San Francisco, CA
  • NPI 1164609962
  Care Compare affiliation

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

{
    "created_epoch": "1585958400000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1789344000000",
    "number": "1770112492",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "300 PASTEUR DR",
            "city": "STANFORD",
            "state": "CA",
            "postal_code": "943052200",
            "telephone_number": "650-723-4000"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "300 PASTEUR DR",
            "city": "STANFORD",
            "state": "CA",
            "postal_code": "943052200",
            "telephone_number": "650-723-4000"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "3288 Moanalua Rd",
            "address_purpose": "LOCATION",
            "city": "Honolulu",
            "state": "HI",
            "postal_code": "968191469",
            "country_code": "US",
            "telephone_number": "310-463-4427",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "1001 Potrero Ave Bldg 5",
            "address_purpose": "LOCATION",
            "city": "San Francisco",
            "state": "CA",
            "postal_code": "941103518",
            "country_code": "US",
            "telephone_number": "628-206-3409",
            "fax_number": "415-206-3112",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "MERZ-HERRALA",
        "first_name": "ALLISON",
        "middle_name": "ALDEN",
        "credential": "MD",
        "sole_proprietor": "YES",
        "sex": "F",
        "enumeration_date": "2020-04-04",
        "last_updated": "2026-09-14",
        "certification_date": "2026-09-14",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207V00000X",
            "taxonomy_group": "",
            "desc": "Obstetrics & Gynecology",
            "state": "CA",
            "license": "A185547",
            "primary": false
        },
        {
            "code": "207VC0300X",
            "taxonomy_group": "",
            "desc": "Obstetrics & Gynecology, Complex Family Planning",
            "state": "CA",
            "license": "A185547",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Hannah Marie Mentjes, PA-C
• Antonio Meola, MD
• Mary P Mercer, M.D.
• Robin F Mercer, PA-C
• Victoria Ann Merrell, P.A.
• Matthew Peter Abe Mesias, M.D.
• Leah Meuter, PA
• Courtney Morgan Meyer, MS, ATC
• Justin Gabriel Meyerowitz, MD
• Samuel Jess Meza, MD

• Obstetrics & Gynecology Physician in Stanford, CA
• Providers in Stanford, CA by specialty
• Obstetrics & Gynecology Physician in California

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Sep 14, 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.
• 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.