Medical emergency?Emergency? Call 911. Nearest emergency roomsNearest ERs

Internal Medicine

Johnny Wu, MD

Works at hospitals in Mission Hills, CA · Fullerton, CA · California

Summary

Johnny Wu, MD (Internal Medicine) is listed by Medicare at 2 hospitals in Mission Hills, CA and Fullerton, CA. NPI 1801356290. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Johnny Wu, 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
YesAccepts Medicare assignment
YesOffers telehealth
7Years since medical school (graduated 2019)
MaleGender (as listed)
Providence Medical FoundationGroup practice

Quick answers

Which hospitals does Johnny Wu work at?
Medicare's official clinician data lists Johnny Wu at 2 hospitals: Providence Holy Cross Medical Center and Providence St. Jude Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Johnny Wu see patients?
Medicare's clinician data lists 7 practice locations, including Fullerton, CA, Orange, CA and Yorba Linda, CA. Call before your visit to confirm the address.
What is Johnny Wu's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Johnny Wu accept Medicare assignment?
Yes. Medicare's clinician data says Johnny Wu accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
Does Johnny Wu offer telehealth?
Medicare's clinician data says Johnny Wu offers telehealth services. Ask the office which visits can be done by video or phone.
What is the phone number for Johnny Wu?
(714) 871-3006, as listed in official Medicare / NPI Registry data.
What is Johnny Wu's NPI number?
1801356290. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Johnny Wu works

Medicare's Facility Affiliation Data lists Johnny Wu at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Johnny Wu is enrolled with Medicare (CMS data updated 2026-10-02). The first 5 of 7; the Medicare profile lists all.

Group practices

Medicare enrollment lists Johnny Wu as a member of this group (CMS data updated 2026-10-02).

  • Providence Medical Foundation1,466 clinicians in the group

Specialties

Find other Internal Medicine doctors in California →

Other internal medicine doctors in Fullerton

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

All internal medicine doctors in Fullerton →

Clinician information

CredentialMD
Graduation year2019
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1801356290
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. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians