Quick answers
- Which hospitals does John D. McCarthy Jr. work at?
- Medicare's official clinician data lists John D. McCarthy Jr. at 2 hospitals: PIH Health Hospital-Whittier and Whittier Hospital Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does John D. McCarthy Jr. see patients?
- Medicare's clinician data lists 3 practice locations, including Whittier, CA, Hacienda Heights, CA and Torrance, CA. Call before your visit to confirm the address.
- What is John D. McCarthy Jr.'s specialty?
- Medicare lists Infectious Disease as the primary specialty, and also Internal Medicine.
- Does John D. McCarthy Jr. accept Medicare assignment?
- Yes. Medicare's clinician data says John D. McCarthy Jr. 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.
- What is the phone number for John D. McCarthy Jr.?
- (562) 698-0811, as listed in official Medicare / NPI Registry data.
- What is John D. McCarthy Jr.'s NPI number?
- 1679650923. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where John D. McCarthy Jr. works
Medicare's Facility Affiliation Data lists John D. McCarthy Jr. at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- PIH Health Hospital-WhittierWhittier, CA · Acute Care Hospital · CCN 050169
- Whittier Hospital Medical CenterWhittier, CA · Acute Care Hospital · CCN 050735
Practice locations
Addresses where John D. McCarthy Jr. is enrolled with Medicare (CMS data updated 2026-10-02).
- 12401 Washington BlvdWhittier, CA 90602 (562) 698‑0811
- 1850 S Azusa Ave, Suite 200Hacienda Heights, CA 91745
- PO Box, Suite 3129Torrance, CA 90510
Specialties
- Infectious Diseaseprimary
- Internal Medicinealso
Other infectious disease doctors in California
Clinicians with the same Medicare primary specialty in California — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of California, Geffen School Of Medicine |
| Graduation year | 1981 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1679650923 |
| Corrections | Report 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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians