NPIMap

Individual provider Active NPI

Ashish Atreja, MD

  • Gastroenterology Physician
  • Stanford, CA
National Provider Identifier
1831152883
Registry record updated Jan 22, 2026
On this page

Key facts

NPPES NPI Registry
Primary specialty
Gastroenterology PhysicianTaxonomy code 207RG0100X
License
C184563 Issued in CA
Practice address
300 Pasteur Dr
Stanford, CA 94305-2200
Phone
(650) 723-4000
NPI assigned
Apr 10, 2006
Sex
Male
Sole proprietor
Yes

NPPES NPI Registry

Updated by the provider on Jan 22, 2026

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

Specialties & licenses 4

Specialty (taxonomy)CodeLicenseStatePrimary
Internal Medicine Physician 207R00000X 35082919 OH
Gastroenterology Physician 207RG0100X 265164 NY
Gastroenterology Physician 207RG0100X C184563 CA Primary
Internal Medicine Physician 207R00000X C184563 CA

Addresses

Primary practice location

300 Pasteur Dr
Stanford, CA 94305-2200

Mailing address

300 Pasteur Dr
Stanford, CA 94305-2200
Phone (650) 723-4000

Other practice location 1

5 E 98th St
New York, NY 10029-6501
Phone (212) 241-4299

Medicare participation

Medicare enrollment files
Medicare fee-for-service enrollment
Enrolled in NY, CA2 enrollments
Eligible to order & refer
  • Part B services
  • Medical equipment
  • Home health
  • Power mobility devices
  • Hospice
Green means eligible to order or refer.

Enrollment records 2

Enrollment IDStateProvider typePAC IDDetails
I20121017000304 NY Practitioner - Gastroenterology 6901873793 Reassigns benefits to 1 organization
I20241106003370 CA Practitioner - Preventive MedicinePractitioner - GastroenterologyPractitioner - Internal Medicine 6901873793 Reassigns benefits to 5 organizations

Care Compare profile

Medicare Care Compare
Specialty
Preventive MedicineAlso: Gastroenterology, Internal Medicine
Education
Other, 1999
Medicare assignment
Accepts the Medicare-approved amount as payment in full
Group practices
Stanford Health CareGroup PAC ID 6709797491, 3,152 clinicians

Practice addresses (Care Compare)

300 Pasteur Dr
Stanford, CA 94305-2200
Phone (650) 723-4000

Hospital & facility affiliations

  • Stanford Health Care Hospital, Stanford, CA, CCN 050441
  • University of California Davis Medical Center Hospital, Sacramento, CA, CCN 050599

Merit-based Incentive Payment System (MIPS)

Final score
83.15 of 100Reported as group
Quality
64.8
Promoting interoperability
100
Improvement activities
40
Cost
68.65

Procedures performed for Medicare patients

ProcedureNumber of procedures
Colonoscopy1-10
Upper gastrointestinal (GI) endoscopy for acid reflux1-10

National Provider Directory

National Provider Directory
Medicare enrollment (NPD)
Enrolled
Credentials
Doctor of Medicine

State licenses

LicenseStateTypeSpecialty
35082919OHMDInternal Medicine Physician
C184563CAMDGastroenterology Physician

Practice roles

OrganizationSpecialtyStatusNew patients
LPCH Medical Group Div of Lucile CurrentSince Dec 17, 2025 Accepting new patients
Regents of the University of California CurrentSince Aug 22, 2024 Accepting new patients
Fusioncareai-Ca, P.C. CurrentSince May 27, 2026 Accepting new patients
Fusioncareai-Ca, P.C. CurrentSince May 27, 2026 Accepting new patients
Regents of the University of California Current Accepting new patients
Stanford Health Care Internal Medicine CurrentSince Dec 17, 2025 Accepting new patients
Regents of the University of California CurrentSince Aug 22, 2024 Accepting new patients
Regents of the Univ of Ca Gastroenterology CurrentSince Aug 22, 2024 Accepting new patients
Regents of the University of California Current Accepting new patients
Regents of the Univ of Ca CurrentSince Dec 1, 2020 Accepting new patients
Icahn School of Medicine at Mount Sinai Gastroenterology CurrentSince Aug 1, 2012 Accepting new patients
Regents of the Univ of Ca Current Accepting new patients
Stanford Health Care CurrentSince Dec 17, 2025 Accepting new patients
Icahn School of Medicine at Mount Sinai CurrentSince Aug 1, 2012 Accepting new patients
Lake Hospital System Inc. Past Accepting new patients
Lake Hospital System Past Accepting new patients
Lake Hospital System Inc Past Accepting new patients

Locations

2660 W Covell Blvd
Davis, CA 95616
Phone (530) 747-3000

8110 Laguna Blvd
Elk Grove, CA 95758
Phone (916) 683-3955

5800 Hollis St
Emeryville, CA 94608
Phone (510) 806-2100

271 Turn Pike Dr
Folsom, CA 95630
Phone (916) 985-9200

725 Welch Rd
Palo Alto, CA 94304
Phone (650) 497-8979

10850 White Rock Rd
Rancho Cordova, CA 95670

550 W Ranch View Dr
Rocklin, CA 95765
Phone (916) 295-5700

2400 Del Paso Rd
Ste 145
Sacramento, CA 95834
Phone (916) 928-3940

4860 Y St
Sacramento, CA 95817
Phone (916) 734-2700

3160 Folsom Blvd
Ste 3500
Sacramento, CA 95816
Phone (916) 734-0779

300 Pasteur Dr
Stanford, CA 94305
Phone (650) 498-5710

5 E 98th St
New York, NY 10029
Phone (212) 241-3986

150 E 42nd St
Fl 10
New York, NY 10017
Phone (646) 605-8119

Ownership & related parties

All facility ownership & control disclosures 4

Facilities whose Medicare enrollment lists this provider’s PECOS associate ID as an owner or managing party.

FacilityTypeRoleSince
UC Davis Medical Center - Rehab UnitSacramento, CA, CCN 05T599 Hospital W-2 Managing Employee Dec 1, 2020
University of California Davis - TransplantSacramento, CA, CCN 059808 Hospital W-2 Managing Employee Dec 1, 2020
UC Davis Home Care ServicesRancho Cordova, CA, CCN 557006 Home health agency Corporate Officer
W-2 Managing Employee		 Dec 1, 2020
Dec 1, 2020
Hospice Program - Ucd Med CtrRancho Cordova, CA, CCN 051560 Hospice W-2 Managing Employee Dec 1, 2020

Owned or controlled facilities with NPI records 4

Facilities whose Medicare enrollment lists this provider as an owner, officer, director or managing party.

Organizations & group practices 20

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.

View all 20

Hospital & facility affiliations 8

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

NPI Registry JSON

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

{
    "created_epoch": "1144627200000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1769040000000",
    "number": "1831152883",
    "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": "5 E 98th St",
            "address_purpose": "LOCATION",
            "city": "New York",
            "state": "NY",
            "postal_code": "100296501",
            "country_code": "US",
            "telephone_number": "212-241-4299",
            "fax_number": "212-426-5108",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "ATREJA",
        "first_name": "ASHISH",
        "credential": "MD",
        "sole_proprietor": "YES",
        "sex": "M",
        "enumeration_date": "2006-04-10",
        "last_updated": "2026-01-22",
        "certification_date": "2026-01-22",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207R00000X",
            "taxonomy_group": "",
            "desc": "Internal Medicine",
            "state": "OH",
            "license": "35082919",
            "primary": false
        },
        {
            "code": "207RG0100X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Gastroenterology",
            "state": "NY",
            "license": "265164",
            "primary": false
        },
        {
            "code": "207RG0100X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Gastroenterology",
            "state": "CA",
            "license": "C184563",
            "primary": true
        },
        {
            "code": "207R00000X",
            "taxonomy_group": "",
            "desc": "Internal Medicine",
            "state": "CA",
            "license": "C184563",
            "primary": false
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

Other providers in Stanford, CA

Sources for this page

Verify at the official NPI Registry.