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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Alexander Si Nguyen, M.D.

Pain Medicine (Anesthesiology) Physician in Seattle, WA · enumerated 2017 · practices at Seattle Extracorporeal.

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

National Provider Identifier

1487186581

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Registry record

Entity type Individual (Type 1)
Name Dr. Alexander Si Nguyen
Credential M.D.
Sex Male
Practice address 925 Seneca Street, Mail Stop H8-Gme, Seattle, WA, 98101
Phone (206) 583-6079
Enumeration date Mar 29, 2017
Last updated in NPPES Aug 21, 2025

Taxonomy & licenses

207L00000X Anesthesiology Physician Allopathic & Osteopathic Physicians · License 317013-01 (NY) Secondary
207L00000X Anesthesiology Physician Allopathic & Osteopathic Physicians · License 036176521 (IL) Secondary
207LP2900X Pain Medicine (Anesthesiology) Physician Allopathic & Osteopathic Physicians · License 317013-01 (NY) 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

Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Alexander Nguyen?
Alexander Nguyen is registered in NPPES with the primary taxonomy of Pain Medicine (Anesthesiology) Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-08-21.