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Rustan J Wiersma, MD

Otolaryngology Physician in Onalaska, WI · enumerated 2005 · practices at Mayo Clinic Hospital-Rochester.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1417947540

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Registry record

Entity type Individual (Type 1)
Name Rustan J Wiersma
Credential MD
Sex Male
Practice address 191 Theatre Rd, Onalaska, WI, 54650
Phone (608) 392-5000
Enumeration date Oct 28, 2005
Last updated in NPPES Apr 2, 2012

Taxonomy & licenses

207Y00000X Otolaryngology Physician Allopathic & Osteopathic Physicians · License 23302 (WI) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What is the NPI number for Rustan Wiersma?
The National Provider Identifier (NPI) for Rustan Wiersma is 1417947540, a Type 1 (individual) record in the CMS NPPES registry.
Where does Rustan Wiersma practice?
The practice location on file with NPPES is in Onalaska, WI. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-04-02.