Doctor profile · Federal record

Dr. Nathan Nguyen, M.D.

Internal Medicine Physician (CMS: Internal Medicine) · Critical Care Medicine (Internal Medicine) Physician · Walnut Creek, CA

  • NPI 1861636615
  • Accepts Medicare
  • 19 yrs in practice
  • Licensed in 2 states
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
1425 S Main St, Medical Office Building 1St Floor
Walnut Creek, CA 945965318
(925) 295-4050
Mailing address
4867 W Sunset Blvd
Los Angeles, CA 900275969

Credentials & registration

NPPES · NUCC
NPI registered
April 2009 — 17 yrs on file
Profile last updated
November 30, 2021
Year of graduation
2007 — 19 yrs since
Specialty taxonomy
207R00000X — NUCC code
State licenses (2)
California #A107250 · Oregon #154500

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1861636615. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
25
Distinct HCPCS
1
Medicare allowed
$5,546
HCPCS Description Services Patients Avg allowed
99291 Critical care, first 30-74 minutes 25 13 $222

In context: peer comparison

Among 44 peers in this city , average services per provider: 260. This provider delivers 0.1× the peer median.

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Nathan Nguyen's medical specialty?
Dr. Nathan Nguyen practices Internal Medicine Physician in Walnut Creek, CA.
Where does Dr. Nathan Nguyen practice?
Dr. Nathan Nguyen practices at 1425 S Main St, Walnut Creek, CA 945965318. Office phone: 9252954050.
What is Dr. Nathan Nguyen's NPI?
Dr. Nathan Nguyen's National Provider Identifier (NPI) is 1861636615, issued by NPPES.
Does Dr. Nathan Nguyen accept Medicare assignment?
Yes. Dr. Nathan Nguyen accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Nathan Nguyen commonly perform?
Top Medicare-reported procedures in 2023: Critical care (HCPCS 99291). Source: CMS Medicare Physician & Other Practitioners file.