NPIMap

Individual provider Active NPI

Ngassa A Mssika, DO

  • Emergency Medicine Physician
  • Oshkosh, WI
National Provider Identifier
1932410461
Registry record updated Jan 8, 2026
On this page

Key facts

NPPES NPI Registry
Primary specialty
Emergency Medicine PhysicianTaxonomy code 207P00000X
License
81255 Issued in WI
Practice address
855 N Westhaven Dr
Oshkosh, WI 54904-7668
Phone
(920) 303-8700
NPI assigned
Jun 30, 2010
Last updated
Jan 8, 2026By the provider in NPPES
Sex
Male
Sole proprietor
No

NPPES NPI Registry

Updated by the provider on Jan 8, 2026

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

Specialties & licenses 1

Specialty (taxonomy)CodeLicenseStatePrimary
Emergency Medicine Physician 207P00000X 81255 WI Primary

Addresses

Primary practice location

855 N Westhaven Dr
Oshkosh, WI 54904-7668

Mailing address

PO Box 735044
Chicago, IL 60673-5044
Phone (920) 303-8700

Other practice location 1

164 N Broadway
Green Bay, WI 54303-2728
Phone (920) 490-9046

Other practice location 2

1700 W Stout St
Rice Lake, WI 54868-5000
Phone (715) 387-5511

Medicare participation

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

Enrollment records 1

Enrollment IDStateProvider typePAC IDDetails
I20231018002782 WI Practitioner - Emergency Medicine 5991984189 Reassigns benefits to 11 organizations

Care Compare profile

Medicare Care Compare
Specialty
Emergency Medicine
Education
Other, 2020
Medicare assignment
Accepts the Medicare-approved amount as payment in full
Group practices
MCHS Hospitals IncGroup PAC ID 5698071173, shared by 28 NPIs, 1,195 clinicians
Aurora Medical Group, Inc.Group PAC ID 6709794258, 3,764 clinicians

Practice addresses (Care Compare)

1000 N Oak Ave
Marshfield, WI 54449-5703
Phone (715) 387-5511

1700 W Stout St
Rice Lake, WI 54868-5000
Phone (715) 236-6133

4100 State Hwy 66
Stevens Point, WI 54482-8410
Phone (715) 997-6000

440 24TH S
Suite 100
Wisconsin Rapids, WI 54494-1914
Phone (715) 424-8625

440 24TH St S
Wisconsin Rapids, WI 54494-1914
Phone (715) 751-6200

855 N Westhaven Dr
Oshkosh, WI 54904-7668
Phone (920) 303-8700

9576 Hwy 70
Minocqua, WI 54548-9067
Phone (715) 358-1710

Hospital & facility affiliations

National Provider Directory

National Provider Directory
Medicare enrollment (NPD)
Enrolled
Credentials
Doctor of Osteopathy, Physician Assistant

State licenses

LicenseStateTypeSpecialty
81255WIMDEmergency Medicine Physician

Practice roles

OrganizationSpecialtyStatusNew patients
Memorial Hospital Inc CurrentSince Oct 18, 2023 Accepting new patients
Lakeview Medical Center Inc of Rice Lake CurrentSince Oct 18, 2023 Accepting new patients
MCHS Hospitals Inc Emergency Medicine Current Accepting new patients
Flambeau Hospital Inc CurrentSince Oct 18, 2023 Accepting new patients
Beaver Dam Community Hospitals Inc CurrentSince Oct 18, 2023 Accepting new patients
Memorial Hospital Inc CurrentSince Oct 18, 2023 Accepting new patients
MCHS Hospitals, Inc. CurrentSince Oct 18, 2023 Accepting new patients
MCHS Hospitals Inc CurrentSince Oct 18, 2023 Accepting new patients
Flambeau Hospital Inc CurrentSince Oct 18, 2023 Accepting new patients
Black River Health Inc Current Accepting new patients
Marshfield Clinic Inc CurrentSince Oct 18, 2023 Accepting new patients
MCHS Hospitals Inc Current Accepting new patients
Beaver Dam Community Hospitals Inc CurrentSince Oct 18, 2023 Accepting new patients
Aurora Medical Group, Inc. Past Accepting new patients

Locations

705 S University Ave
Beaver Dam, WI 53916
Phone (920) 885-6090

711 W Adams St
Blk River Fls, WI 54615
Phone (715) 284-3604

1000 Starr Ave
Eau Claire, WI 54703
Phone (715) 858-4850

3501 Golf Rd
Eau Claire, WI 54701
Phone (715) 858-4200

1000 N Oak Ave
Marshfield, WI 54449
Phone (715) 387-5111

1000 N Oak Ave
Fl 2
Marshfield, WI 54449

1102 S Center Ave
Merrill, WI 54452
Phone (715) 536-3399

N3708 River Ave
Neillsville, WI 54456
Phone (715) 743-3101

1700 W Stout St
Rice Lake, WI 54868
Phone (715) 236-6133

Interoperability endpoints

  • Direct secure messaging: nmssika63048@aurora.direct-ci.com

Organizations & group practices 15

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.

View all 15

Hospital & facility affiliations 7

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": "1277856000000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1767830400000",
    "number": "1932410461",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "PO BOX 735044",
            "city": "CHICAGO",
            "state": "IL",
            "postal_code": "606735044",
            "telephone_number": "920-303-8700"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "855 N WESTHAVEN DR",
            "city": "OSHKOSH",
            "state": "WI",
            "postal_code": "549047668",
            "telephone_number": "920-303-8700"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "164 N Broadway",
            "address_purpose": "LOCATION",
            "city": "Green Bay",
            "state": "WI",
            "postal_code": "543032728",
            "country_code": "US",
            "telephone_number": "920-490-9046",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "1700 W Stout St",
            "address_purpose": "LOCATION",
            "city": "Rice Lake",
            "state": "WI",
            "postal_code": "548685000",
            "country_code": "US",
            "telephone_number": "715-387-5511",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "MSSIKA",
        "first_name": "NGASSA",
        "middle_name": "A",
        "credential": "DO",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2010-06-30",
        "last_updated": "2026-01-08",
        "certification_date": "2026-01-08",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207P00000X",
            "taxonomy_group": "",
            "desc": "Emergency Medicine",
            "state": "WI",
            "license": "81255",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

Other providers in Oshkosh, WI

Sources for this page

Verify at the official NPI Registry.