Active NPI
Gurdon H Hamilton, MD
- Internal Medicine Physician
- Marshfield, WI
National Provider Identifier
1720188931
On this page
Key facts
NPPES NPI Registry- Primary specialty
- Internal Medicine Physician
- License
- 19781
- Practice address
- 1000 N Oak Ave
H4W a & Dr
Marshfield, WI 54449 - Phone
- (715) 387-7090
- NPI assigned
- Sep 25, 2006
- Sex
- Male
- Sole proprietor
- No
NPPES NPI Registry
Registry information is reported by the provider to CMS and is not verified. About this source
Specialties & licenses 2
| Specialty (taxonomy) | Code | License | State | Primary |
|---|---|---|---|---|
| Internal Medicine Physician | 207R00000X | 19781 | WI | Primary |
| Addiction Medicine (Internal Medicine) Physician | 207RA0401X | 19781 | WI |
Addresses
Primary practice location
1000 N Oak Ave
H4W a & Dr
Marshfield, WI 54449
Mailing address
1000 N Oak Ave
H4W a & Dr
Marshfield, WI 54449-5777
Other identifiers 1
| Identifier | Type | State | Issuer |
|---|---|---|---|
| 31245000 | Medicaid | WI |
Medicare participation
Medicare enrollment files- Medicare fee-for-service enrollment
- Not listed in the public Medicare enrollment file
National Provider Directory
National Provider Directory- Medicare enrollment (NPD)
- Enrolled
- Credentials
- Doctor of Medicine
NPI Registry JSON
The complete NPPES record for this NPI in the NPI Registry API format.
{
"created_epoch": "1159142400000",
"enumeration_type": "NPI-1",
"last_updated_epoch": "1757548800000",
"number": "1720188931",
"addresses": [
{
"country_code": "US",
"country_name": "United States",
"address_purpose": "MAILING",
"address_type": "DOM",
"address_1": "1000 N OAK AVE",
"address_2": "H4W A & DR",
"city": "MARSHFIELD",
"state": "WI",
"postal_code": "544495777"
},
{
"country_code": "US",
"country_name": "United States",
"address_purpose": "LOCATION",
"address_type": "DOM",
"address_1": "1000 N OAK AVE",
"address_2": "H4W A & DR",
"city": "MARSHFIELD",
"state": "WI",
"postal_code": "54449",
"telephone_number": "715-387-7090"
}
],
"practiceLocations": [],
"basic": {
"last_name": "HAMILTON",
"first_name": "GURDON",
"middle_name": "H",
"credential": "MD",
"sole_proprietor": "NO",
"sex": "M",
"enumeration_date": "2006-09-25",
"last_updated": "2025-09-11",
"status": "A"
},
"taxonomies": [
{
"code": "207R00000X",
"taxonomy_group": "",
"desc": "Internal Medicine",
"state": "WI",
"license": "19781",
"primary": true
},
{
"code": "207RA0401X",
"taxonomy_group": "",
"desc": "Internal Medicine, Addiction Medicine",
"state": "WI",
"license": "19781",
"primary": false
}
],
"identifiers": [
{
"code": "05",
"desc": "MEDICAID",
"issuer": null,
"identifier": "31245000",
"state": "WI"
}
],
"endpoints": [],
"other_names": []
}
Other providers in Marshfield, WI
Sources for this page
- NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Sep 11, 2025; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
- National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.