Dr. James Nash , DO
Internal Medicine โข Marshfield, WI
1000 N Oak Ave
Marshfield, WI 54449
This profile restates public CMS/NPPES data; T-MedInfo gives no medical advice — consult a licensed professional, and call 911 for emergencies.
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NPI assigned on July 9, 2014; this date does not establish years in practice.
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Published CMS data list 663 Original Medicare Part B services in 2024.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024. Published rows only; this is not a quality measure.
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Published Part B service records, 2024:
- 99214 โ Established patient outpatient office visit: 322 service units.
- G0439 โ Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit: 130 service units.
- G2211 โ Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's: 102 service units.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024. Units differ by code; these are not visits or a measure of quality.
CPTยฎ only copyright 2023 American Medical Association. All rights reserved. Service names are shortened from CPT Consumer Friendly Descriptors (CMS data, 2024). CPT notice
See all 5 records in the table ยท Guide: How to read Medicare Part B data
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Published CMS data list 10,122 Medicare Part D prescriptions, including refills, in 2024.
Source: CMS, Medicare Part D Prescribers โ by Provider and Drug, 2024. Published rows only; this is not a quality measure.
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Published Part D records, 2024:
- Atorvastatin Calcium โ 658 prescription fills, including refills.
- Lisinopril โ 484 prescription fills, including refills.
- Omeprazole โ 422 prescription fills, including refills.
Source: CMS, Medicare Part D Prescribers โ by Provider and Drug, 2024. Drug names come from pharmacy claims. Listing a drug here is not an endorsement or a recommendation.
See all 158 records in the table ยท Guide: How to read Medicare Part D prescriber data
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More Medicare Part B services than 85% of clinicians listed under Internal Medicine in Marshfield, WI (2024, 28 clinicians with data). Median for this group: 243. Middle half: 146 to 454.
Close to the middle for Medicare Part B services among clinicians listed under Internal Medicine in Wisconsin (2024, 1,010 clinicians with data). Median for this group: 572. Middle half: 266 to 1,020.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024. Billing and prescribing volume is not a quality rating.
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Medicare Part B services went from 1,875 in 2020 to 663 in 2024.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2020โ2024.
Practice Location & Contact Primary Location
1000 N Oak Ave
Marshfield, WI 54449
Matched by practice address or phone in NPPES. A shared address or phone does not confirm that this clinician works there.
NPPES lists 1 additional practice-address record in Des Moines, IA. See the list
Source: CMS NPPES NPI Registry, practice location records; release date unavailable.
CMS Doctors and Clinicians lists 2 distinct group names: Aspirus Rhinelander And Tomahawk Hospitals And Clinics, Inc.; Mchs Hospitals Inc. See the list
Source: CMS Doctors and Clinicians National Downloadable File, release date unavailable.
Listings do not confirm current availability, employment or a shared ownership network.
Medicare Profile & Education
Source: CMS Doctors and Clinicians National Downloadable File
Lake Erie College Of Osteopathic Medicine, Erie
2014
What Public CMS Data Show
Internal Medicine: NPPES taxonomy is a reported classification, not proof of board certification.
Medicare patients
297 people with Original Medicare in 2024
It gives a sense of how many people with Medicare this clinician treated that year.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider, 2024.
Medicare-allowed amount
About $57,035 in 2024
The total amount Medicare approved for these services in 2024. It includes what Medicare paid and what patients or their other insurance owed, such as the deductible and coinsurance.
It shows the total cost of this clinician's Original Medicare services under Medicare's fee rules.
What this does not show: Medicare-allowed amount
This is not the clinician's income. Part of it can go to a clinic or group practice, staff, equipment or drugs. It is not the price you will pay.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024.
Paid by Medicare
About $43,173 in 2024
The part of the Medicare-allowed amount that Medicare itself paid in 2024, after patients' deductibles and coinsurance.
The gap between the allowed amount and this number is roughly what patients and their other insurance paid.
What this does not show: Paid by Medicare
This is not the clinician's income and not a measure of quality.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024.
30-day fills
23,272 standardized 30-day fills in 2024
CMS converts prescriptions to 30-day supplies so they can be compared. A 90-day prescription counts as about three 30-day fills.
What this does not show: 30-day fills
It is not a count of patients and not a measure of quality.
Part D drug cost
$950,301 in 2024
The total cost of these prescriptions in 2024, paid by Medicare drug plans, patients and other payers together.
It shows the total spending on drugs this clinician prescribed, not what any one patient paid.
What this does not show: Part D drug cost
A higher cost often reflects the type of medicines a specialty uses. It is not your out-of-pocket cost and not a measure of quality.
Source: CMS, Medicare Part D Prescribers โ by Provider and Drug, 2024.
Industry payments (Open Payments)
Fewer than 11 payment records totaling $14.75 in 2025
Drug and medical device companies must report certain payments to doctors and some other clinicians to CMS, such as meals, travel, speaking fees or research funding.
It shows reported financial ties between this clinician and companies. You can ask your clinician about them.
These records are submitted by drug and medical device companies, and a reported payment does not necessarily mean the financial relationship is improper.
General: payments not tied to research, such as meals, travel, consulting or speaking fees.
A reported payment does not necessarily mean the financial relationship is improper. Research payments can go to a hospital or university for a study the clinician leads, not to the clinician personally. Clinicians can dispute records with the company that reported them.
Source: CMS Open Payments, program year 2025.
Years since graduation
12 years (graduated 2014)
CMS Doctors and Clinicians data list 2014 as the year this clinician finished professional school.
It tells you roughly how long ago the clinician finished school.
What this does not show: Years since graduation
It is not the number of years in practice, and more years does not mean better care.
Source: CMS Doctors and Clinicians National Downloadable File.
NPI first issued
2014
The year this clinician's National Provider Identifier (NPI) was issued. An NPI is a unique 10-digit ID that US health care providers use for billing.
What this does not show: NPI first issued
NPIs have been issued only since 2005, so this year is not necessarily when the clinician started practicing.
Source: CMS NPPES NPI Registry.
Accepts Medicare assignment
CMS data list this clinician as accepting Medicare assignment. This means agreeing to take the Medicare-approved amount as full payment for covered services.
With Original Medicare, you usually pay only your deductible and coinsurance, and the office sends the claim to Medicare for you.
Medicare assignment applies to Original Medicare. It does not tell you whether the clinician is in a Medicare Advantage plan's network, accepts other insurance, or is taking new patients.
Source: CMS Doctors and Clinicians; Medicare.gov, โDoes your provider accept Medicare as full payment?โ
Telehealth (some services)
Recent Medicare claims show this clinician provided some services by telehealth, such as a video or phone visit.
You may be able to have some visits without going to the office. Ask which visits can be done by telehealth.
What this does not show: Telehealth (some services)
It does not mean all services are offered by telehealth, or that telehealth is covered by your plan.
Source: CMS, Telehealth Indicator on Medicare Care Compare (fact sheet, January 2023); CMS Doctors and Clinicians.
Enrolled in Medicare (PECOS)
Dr. Nash has a Medicare enrollment record in PECOS, the CMS system clinicians use to enroll so they can bill Medicare or order services for people with Medicare.
It does not show whether the clinician accepts assignment, is in your plan's network, or is taking new patients.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Can order Medicare-covered services
CMS lists Dr. Nash as eligible to order or refer Medicare Part B clinical laboratory and imaging services, durable medical equipment (DME) and home health services for people with Medicare.
Medicare pays for these items and services only when they are ordered by an eligible clinician.
What this does not show: Can order Medicare-covered services
It does not mean the clinician offers these services directly.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Compared with the same specialty in Marshfield and Wisconsin
Billing and prescribing volume is not a quality rating.
Medicare Part B services
More Medicare Part B services than 85% of clinicians listed under Internal Medicine in Marshfield, WI (2024, 28 clinicians with data). Median for this group: 243. Middle half: 146 to 454.
Close to the middle for clinicians listed under Internal Medicine in Wisconsin (2024, 1,010 clinicians with data). Median for this group: 572. Middle half: 266 to 1,020.
Medicare-allowed amount
A higher Medicare-allowed amount than 80% of clinicians listed under Internal Medicine in Marshfield, WI (2024, 28 clinicians with data). Median for this group: $22,738. Middle half: $13,747 to $40,751.
Close to the middle for clinicians listed under Internal Medicine in Wisconsin (2024, 1,010 clinicians with data). Median for this group: $49,332. Middle half: $25,625 to $85,764.
Paid by Medicare
A higher Medicare payment amount than 80% of clinicians listed under Internal Medicine in Marshfield, WI (2024, 28 clinicians with data). Median for this group: $16,820. Middle half: $9,713 to $32,898.
Close to the middle for clinicians listed under Internal Medicine in Wisconsin (2024, 1,010 clinicians with data). Median for this group: $38,120. Middle half: $18,776 to $65,615.
Medicare Part D prescriptions
More Part D prescriptions than 95% of clinicians listed under Internal Medicine in Marshfield, WI (2024, 30 clinicians with data). Median for this group: 2,383. Middle half: 185 to 4,557.
More Part D prescriptions than 85% of clinicians listed under Internal Medicine in Wisconsin (2024, 1,164 clinicians with data). Median for this group: 2,178. Middle half: 139 to 7,601.
Part D drug cost
A higher Part D drug cost than 95% of clinicians listed under Internal Medicine in Marshfield, WI (2024, 30 clinicians with data). Median for this group: $148,578. Middle half: $7,976 to $312,648.
A higher Part D drug cost than 90% of clinicians listed under Internal Medicine in Wisconsin (2024, 1,164 clinicians with data). Median for this group: $173,642. Middle half: $7,999 to $596,192.
62 active clinicians are listed under Internal Medicine with a practice address in Marshfield, WI (2,078 in Wisconsin).
Addresses are self-reported to NPPES and may be out of date.
Telehealth indicator in Marshfield
14.5% of these 62 clinicians have the CMS telehealth indicator.
38.7% of these 62 clinicians are listed by CMS as accepting Medicare assignment.
CMS data by year
Changes may reflect reporting, coverage or privacy limits, not changes in care quality.
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Medicare Part B services
Medicare Part B services decreased 65% from 1,875 in 2020 to 663 in 2024.
- 2020: 1,875
- 2021: 2,464
- 2022: 4,381
- 2023: 1,564
- 2024: 663
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Medicare-allowed amount
Medicare-allowed amount decreased 33% from $85,209 in 2020 to $57,035 in 2024.
- 2020: $85,209
- 2021: $108,568
- 2022: $137,597
- 2023: $30,596
- 2024: $57,035
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Paid by Medicare
Paid by Medicare decreased 39% from $70,651 in 2020 to $43,173 in 2024.
- 2020: $70,651
- 2021: $89,139
- 2022: $117,726
- 2023: $28,417
- 2024: $43,173
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Medicare Part D prescriptions
Medicare Part D prescriptions decreased 25% from 13,445 in 2020 to 10,122 in 2024.
- 2020: 13,445
- 2021: 14,391
- 2022: 12,409
- 2023: 11,072
- 2024: 10,122
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30-day fills
30-day fills decreased 22% from 29,943 in 2020 to 23,272 in 2024.
- 2020: 29,943
- 2021: 33,014
- 2022: 29,191
- 2023: 25,539
- 2024: 23,272
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Part D drug cost
Part D drug cost decreased 12% from $1,077,490 in 2020 to $950,301 in 2024.
- 2020: $1,077,490
- 2021: $1,305,253
- 2022: $1,127,172
- 2023: $1,019,676
- 2024: $950,301
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Industry payments (Open Payments)
Industry payments (Open Payments) went from $12.28 in 2020 to $14.75 in 2025.
- 2020: $12.28
- 2023: $43.02
- 2025: $14.75
Sources: CMS Medicare Physician & Other Practitioners (2024), CMS Medicare Part D Prescribers (2024), CMS Open Payments (2025), CMS Doctors and Clinicians, CMS NPPES NPI Registry. Specialty names follow the NUCC Health Care Provider Taxonomy.
Text: T-MedInfo ยท Report an error.
Pharma & Medical Device Financial Disclosures
Payments and other transfers of value that drug and medical device companies reported to CMS Open Payments
Program year 2025 (payments made January 1 โ December 31, 2025): fewer than 11 records totaling $14.75.
| Manufacturer | Payment Nature | Product | Type | Amount ($) |
|---|---|---|---|---|
| Bristol Myers Squibb Company |
Education
In-kind items and services
|
ABILIFY | General | $14.75 |
Source: CMS Open Payments, program year 2025, released June 30, 2026.
Performed Procedures & Service Volume
CPTยฎ is a registered trademark of the American Medical Association. CPT codes, descriptions and other data only are copyright 2016โ2023 American Medical Association. All rights reserved. Applicable FARS/HHSARS apply. Descriptions of CPT codes are the AMA's CPT Consumer Friendly Descriptors as published by CMS in the Medicare Physician & Other Practitioners โ by Provider and Service data, 2017โ2024; they are plain-language summaries, not for clinical coding or documentation. HCPCS Level II codes and descriptions are from CMS. Fee schedules, relative value units, conversion factors and/or related components are not assigned by the AMA, are not part of CPT, and the AMA is not recommending their use. The AMA does not directly or indirectly practice medicine or dispense medical services. The AMA assumes no liability for data contained or not contained herein.
| HCPCS Code | Services | Patients | Submitted Charge | Medicare Allowed |
|---|---|---|---|---|
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99214
Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more
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322 | 233 | $264.07 | $90.75 |
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G0439
Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit
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130 | 130 | $341.27 | $122.04 |
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G2211
Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's
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102 | 84 | $71.10 | $15.53 |
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99213
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more
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59 | 53 | $173.33 | $61.69 |
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99215
Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more
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50 | 38 | $402.75 | $134.49 |
Source: CMS Part B by Provider and Service, 2024; services under 11 beneficiaries omitted by CMS. Privacy limits
Submitted charges are billed amounts, not a price quote for your visit.
Medicare Part D Prescribing Profile & Medications
Medicare Part D prescriptions filled, including refills, in 2024.
| Brand Name | Generic Name | Prescriptions | Day Supply | Total Cost | Patients |
|---|---|---|---|---|---|
| Atorvastatin Calcium | Atorvastatin Calcium | 658 | 52,964 | $5,263.92 | 270 |
| Lisinopril | Lisinopril | 484 | 40,201 | $3,014.64 | 194 |
| Omeprazole | Omeprazole | 422 | 32,773 | $5,085.43 | 157 |
| Amlodipine Besylate | Amlodipine Besylate | 379 | 30,909 | $2,326.51 | 149 |
| Metoprolol Succinate | Metoprolol Succinate | 333 | 26,814 | $4,152.26 | 117 |
| Levothyroxine Sodium | Levothyroxine Sodium | 315 | 24,372 | $3,244.16 | 122 |
| Metformin Hcl | Metformin Hcl | 291 | 22,666 | $2,511.73 | 103 |
| Gabapentin | Gabapentin | 289 | 17,095 | $4,517.61 | 84 |
| Losartan Potassium | Losartan Potassium | 279 | 23,790 | $2,310.78 | 117 |
| Hydrochlorothiazide | Hydrochlorothiazide | 225 | 18,682 | $884.33 | 95 |
| Eliquis | Apixaban | 190 | 11,238 | $211,114.84 | 58 |
| Simvastatin | Simvastatin | 185 | 14,774 | $1,400.23 | 64 |
| Tamsulosin Hcl | Tamsulosin Hcl | 176 | 14,486 | $2,004.78 | 75 |
| Metoprolol Tartrate | Metoprolol Tartrate | 170 | 13,960 | $1,085.96 | 67 |
| Warfarin Sodium | Warfarin Sodium | 165 | 12,917 | $2,095.22 | 66 |
| Rosuvastatin Calcium | Rosuvastatin Calcium | 158 | 14,040 | $2,160.99 | 69 |
| Pantoprazole Sodium | Pantoprazole Sodium | 152 | 11,107 | $1,821.41 | 55 |
| Allopurinol | Allopurinol | 145 | 10,588 | $1,234.24 | 47 |
| Potassium Chloride | Potassium Chloride | 139 | 9,620 | $2,660.51 | 46 |
| Sertraline Hcl | Sertraline Hcl | 121 | 9,279 | $1,045.22 | 46 |
| Ozempic | Semaglutide | 121 | 4,574 | $146,810.35 | 23 |
| Hydrocodone-Acetaminophen | Hydrocodone/Acetaminophen | 120 | 2,539 | $2,778.66 | 26 |
| Furosemide | Furosemide | 114 | 8,157 | $680.02 | 51 |
| Tramadol Hcl | Tramadol Hcl | 111 | 2,861 | $833.91 | 30 |
| Pravastatin Sodium | Pravastatin Sodium | 110 | 9,840 | $1,439.30 | 45 |
(top 25 shown)
Source: CMS Part D by Provider and Drug, 2024; rows below 11 claims omitted by CMS; volume isn’t quality. Privacy limits
Specialties & License Numbers Reported to NPPES
Self-certified to NPPES: 2024-02-16NUCC Taxonomy Code: 207R00000X
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
NUCC Taxonomy Code: 207R00000X
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
Medicare (PECOS) Enrollment & Ordering Eligibility
Source: CMS PECOSPRACTITIONER - INTERNAL MEDICINE
I20170818000165
WI
6901022011
Sources: CMS Provider Enrollment and Order and Referring. Medicare enrollment is a billing status, not an accreditation or quality rating.
Medicare Group Practice Enrollments
Source: CMS Doctors and Clinicians National Downloadable File
Mchs Hospitals Inc
1000 N Oak Ave, Marshfield, WI 544495703
Aspirus Rhinelander And Tomahawk Hospitals And Clinics, Inc.
824 Illinois Ave, Stevens Point, WI 544813112
Phone: 7153441600
Mchs Hospitals Inc
2727 Plaza Dr, Marshfield, WI 544495703
Mchs Hospitals Inc
1000 N Oak Ave, Marshfield, WI 544495703
Phone: 7153875511
Secondary Practice Locations
1111 6th Ave
Des Moines, IA 503142613
Phone: 5156438678
Clinicians Sharing This Practice Address or Phone
Clinicians sharing this NPPES address, phone or fax; a shared contact does not mean they work together.
Nurse Anesthetist, Certified Registered
Certified Registered Nurse Anesthetist
Orthopaedic Surgery
Doctor of Medicine (M.D.)
Surgery - Trauma Surgery
Doctor of Medicine (M.D.)
Pathology - Anatomic Pathology & Clinical Pathology
Doctor of Medicine (M.D.)
Nurse Practitioner - Gerontology
Nurse Practitioner
Nurse Practitioner
Nurse Practitioner
Career & Practice History Timeline
Changes recorded in monthly NPPES data files: addresses, names, credentials, specialties and NPI status
Registered at 1000 N OAK AVE, MARSHFIELD, WI 54449 (Tel: 7153875511)
Registered at 1000 N OAK AVE, MARSHFIELD, WI 544495703 (Tel: 7153875511)
NPI status registered as active in NPPES database
Registered at 1111 6TH AVE, DES MOINES, IA 503142613 (Tel: 5156438678)
Registered at 1111 6TH AVE, DES MOINES, IA 503142613 (Tel: 5156438678)
Recorded as JAMES NASH, DO
Internal Medicine (license number reported to NPPES: IA R-10126)
First registered as active Individual Practitioner in NPPES Database.
NPI Administrative Meta
Other Internal Medicine Providers in Marshfield
- Dr. Jessica Marshall, MD
- Dr. Analise Hanneman, MD
- Dr. Frederick Hernaez, MD
- Dr. John Olson, MD
- Dr. Muhammad Haleem, MD
- Dr. Tekabe Birhane, MD
More public profiles in Wisconsin
Directory navigation, in NPI number order.
- Jason Pohl, DDS Dentist - General Practice ยท Appleton
- Nicole Kujawa, PA Physician Assistant ยท Oconomowoc
- James Bell, MD Family Medicine ยท Green Bay
- Elizabeth Cogbill, MD Internal Medicine - Geriatric Medicine ยท La Crosse
- Marc Durette, MD Physical Medicine & Rehabilitation ยท Rhinelander
- Kimberly Woyach, DNP Nurse Practitioner ยท Mount Pleasant
- Diana Soltis-Friesner, LCSW Social Worker - Clinical ยท Muskego
- Michelle Rejman, MD Family Medicine ยท Sheboygan Falls
- Ann Rohrer, APNP Nurse Practitioner ยท Milwaukee
- Henry Loomans, MD Internal Medicine ยท Oconto Falls
- Andrea Martonffy, MD Family Medicine ยท Madison
- Radu Pirvanescu, MD Internal Medicine ยท Fond Du Lac
Mailing Address
1000 N Oak Ave
Marshfield, WI 544495703
Phone: 7153875511