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Douglas Duffy, MD — NPI 1366542227, Marshfield, WI | NPI Central

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Douglas Duffy, MD

NPI 1366542227 · Nephrology Physician · Marshfield, WI

Provider details

NPI number: 1366542227
Entity type: Individual
Primary specialty: Nephrology PhysicianAllopathic & Osteopathic Physicians
Credential: MD
Sex: Male
Sole proprietor: No
License: 25241 (WI)

Specialties & taxonomies

Nephrology PhysicianPrimary207RN0300XLicense 25241 (WI)
Allopathic & Osteopathic Physicians
Internal Medicine Physician207R00000XLicense 25241 (WI)
Allopathic & Osteopathic Physicians
Nephrology Physician207RN0300XLicense LT15265 (ND)
Allopathic & Osteopathic Physicians

Practice location

1000 N Oak Ave

Marshfield, WI 54449

Phone: (715) 387-5345

Approximate (ZIP-level) locationGet directions

More WI providers

Mailing address

1000 N Oak Ave

Marshfield, WI 54449-5777

Additional practice locations (1)

801 Broadway N
Fargo, ND 58102-3641
Phone: (701) 234-2000

Registry dates

Enumerated: 2006-09-22
Last updated: 2018-08-01

Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.