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Dr. Gretchen Nicole Karstens, MD

Pediatrics Physician in Duluth, MN · enumerated 2006.

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

National Provider Identifier

1669405189

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Registry record

Entity type Individual (Type 1)
Name Dr. Gretchen Nicole Karstens
Credential MD
Sex Female
Practice address 1012 E 2nd St, Duluth, MN, 55805
Phone (218) 249-7870
Fax (218) 249-7801
Enumeration date Jul 8, 2006
Last updated in NPPES Dec 4, 2020

Taxonomy & licenses

208000000X Pediatrics Physician Allopathic & Osteopathic Physicians · License 49164 (MN) 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

Where does Gretchen Karstens practice?
The practice location on file with NPPES is in Duluth, MN. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Gretchen Karstens?
The National Provider Identifier (NPI) for Gretchen Karstens is 1669405189, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2020-12-04.