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Emergency Medicine

Marissa Valenzuela, MD

Sees patients in San Dimas, CA · Los Angeles, CA · California

Summary

Dr. Marissa Valenzuela, MD is an emergency medicine doctor at 180 Via Verde, Suite 100, San Dimas, CA 91773. May accept Medicare assignment. NPI 1588369540. Source: CMS National Downloadable File, updated October 2, 2026.

  • Specialty: Emergency medicine doctor (Medicare lists Emergency Medicine)
  • Address: 180 Via Verde, Suite 100, San Dimas, CA 91773 · Directions (1 more location)
  • Medicare: May accept Medicare assignment
  • Medical school: University Of Southern California Keck School Of Medicine · graduated 2023 (3 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Marissa Valenzuela, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Marissa Valenzuela accept Medicare assignment?
Medicare's clinician data says Marissa Valenzuela may accept Medicare assignment (as of October 2, 2026). Ask the office whether they accept it for your visit.
What is Marissa Valenzuela's NPI number?
1588369540. 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 Marissa Valenzuela is enrolled with Medicare (CMS data updated October 2, 2026).

  • 180 Via Verde, Suite 100San Dimas, CA 91773
  • PO Box, Suite 60259Los Angeles, CA 90060

Specialties

Find other Emergency Medicine doctors in California →

Other emergency medicine doctors in San Dimas

Clinicians with the same Medicare primary specialty in San Dimas, CA — not a recommendation.

All emergency medicine doctors in San Dimas →

Clinician information

CredentialMD
Medical schoolUniversity Of Southern California Keck School Of Medicine
Graduation year2023 (3 years since medical school)
Gender (as listed)Female
Medicare assignmentMay accept for some services
NPI (National Provider Identifier)1588369540
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 October 2, 2026, retrieved October 29, 2026
  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