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Internal Medicine

Si Young An, MD

Sees patients in Santa Clara, CA · Pasadena, CA · California

Summary

Si Young An, MD (Internal Medicine) is enrolled with Medicare at 2 practice locations in Santa Clara, CA and Pasadena, CA. NPI 1285336545. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Si Young An, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Internal MedicinePrimary specialty
May acceptAccepts Medicare assignment
3Years since medical school (graduated 2023)
FemaleGender (as listed)

Quick answers

Where does Si Young An see patients?
Medicare's clinician data lists 2 practice locations, including Santa Clara, CA and Pasadena, CA. Call before your visit to confirm the address.
What is Si Young An's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Si Young An accept Medicare assignment?
Medicare's clinician data says Si Young An may accept Medicare assignment (as of 2026-10-02). Ask the office whether they accept it for your visit.
What is Si Young An's NPI number?
1285336545. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Si Young An is enrolled with Medicare (CMS data updated 2026-10-02).

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Santa Clara

Clinicians with the same Medicare primary specialty in Santa Clara, CA — not a recommendation.

All internal medicine doctors in Santa Clara →

Clinician information

CredentialMD
Graduation year2023
Gender (as listed)Female
Medicare assignmentMay accept for some services
NPI (National Provider Identifier)1285336545
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians