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GEM MEDICAL GROUP CORPORATION
NPI 1689386815
Emergency Medicine in Monterey Park, CA

Active since December 19, 2022
525 N GARFIELD AVE, MONTEREY PARK, CA 91754(626) 573-2222 Get Directions Write a Review

NPPES record last updated: March 25, 2025. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Mar 25, 2025, May 23, 2023, Dec 19, 2022 (3 updates tracked since 2022).

About Gem Medical Group Corporation NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

GEM MEDICAL GROUP CORPORATION (NPI 1689386815), doing business as Gem Medical Group, is a healthcare organization registered as an emergency medicine in Monterey Park, California and active in the NPI registry since December 2022. The organization lists John Chon, Ceo, as its authorized official.

NPPES Registry Identity

NPI1689386815
Entity TypeOrganization
Primary Taxonomy207P00000X
Legal Business NameGEM MEDICAL GROUP CORPORATION
Location Address525 N GARFIELD AVEMonterey Park, CA 91754-1202
Mailing AddressPo Box 25600Pasadena, CA 91185-5600
Phone(626) 573-2222
Organization SubpartNo
Authorized OfficialJohn ChonCeo · (626) 791-5286
Enumeration DateDecember 19, 2022
Last NPPES UpdateMarch 25, 20253 updates tracked since enumeration
NPPES CertifiedMarch 25, 2025
✔ NPI 1689386815 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyEmergency MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207P00000X
Definition
An emergency physician focuses on the immediate decision making and action necessary to prevent death or any further disability both in the pre-hospital setting by directing emergency medical technicians and in the emergency department. The emergency physician provides immediate recognition, evaluation, care, stabilization and disposition of a generally diversified population of adult and pediatric patients in response to acute illness and injury.
525 N GARFIELD AVE, Monterey Park, CA 91754
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Other Names 1

Doing Business AsGem Medical Group

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Gem Medical Group Corporation is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

79

Medicare enrollment records show 79 clinicians reassign Medicare billing to Gem Medical Group Corporation, which bills Medicare for the services they deliver. Of these, 4 practice at this address and 25 within 10 miles. Listed here are the 20 practicing nearest to this location.

Clinicians by Medicare Specialty 5

Emergency Medicine57
Nurse Practitioner15
Family Practice4
Internal Medicine2
General Practice1

Nearest to this location (20)

See all 79
Victoria Dao, FNP-C
Nurse Practitioner
NPI 1497646517
525 N GARFIELD AVE
Monterey Park, CA 91754
(626) 573-2222
✔ PECOS✔ Accepts MedicareSame address
Lisa Xu
Nurse Practitioner
NPI 1902770886
525 N GARFIELD AVE
Monterey Park, CA 91754
(626) 573-2222
✔ PECOSSame address
Vincent Jimena, NP
Nurse Practitioner
NPI 1568788081
525 N GARFIELD AVE
Monterey Park, CA 91754
(909) 629-8088
✔ PECOS✔ Accepts MedicareSame address
Jeremy Williams, M.D.
Emergency Medicine
NPI 1023052230
525 N GARFIELD AVE
Monterey Park, CA 91754
(626) 307-2129
✔ PECOS✔ Accepts MedicareSame address
Tiffany Chung
Nurse Practitioner
NPI 1922604289
525 N GARFIELD AVE
Monterey Park, CA 91754
(626) 573-2222
✔ PECOS✔ Accepts Medicare0.8 mi
Phong Ngo, MD
Emergency Medicine
NPI 1942243449
525 N GARFIELD AVE
Monterey Park, CA 91754
(626) 307-2129
✔ PECOS✔ Accepts Medicare0.8 mi
Rolando Castillo, N.P.
Nurse Practitioner
NPI 1528581519
900 S ATLANTIC BLVD
Monterey Park, CA 91754
(626) 570-9000
✔ PECOS✔ Accepts Medicare1.5 mi
Li Cui
Emergency Medicine
NPI 1093193575
900 S ATLANTIC BLVD
Monterey Park, CA 91754
(323) 788-6538
✔ PECOS✔ Accepts Medicare1.5 mi
Tom Nguyen, DO
Family Practice
NPI 1598729980
9146 E. VALLEY BLVD SUITE A
Rosemead, CA 91770
(626) 571-6908
✔ PECOS3.2 mi
Anh Mai, M.D.
Emergency Medicine
NPI 1376706853
1701 SANTA ANITA AVE
South El Monte, CA 91733
(626) 679-7777
✔ PECOS✔ Accepts Medicare4.8 mi
Syed Zaidi
Emergency Medicine
NPI 1225480932
1701 SANTA ANITA AVE
El Monte, CA 91733
(626) 579-7777
✔ PECOS✔ Accepts Medicare4.8 mi
Weyjuin Chao, M.D.
Emergency Medicine
NPI 1154852218
1701 SANTA ANITA AVE
South El Monte, CA 91733
(626) 579-7777
✔ PECOS✔ Accepts Medicare4.8 mi
John Lin, M.D.
Internal Medicine
NPI 1689602609
1701 SANTA ANITA AVE
South El Monte, CA 91733
(626) 350-7957
✔ PECOS✔ Accepts Medicare4.8 mi
Huma Khan, MD
Emergency Medicine
NPI 1528367174
2079 MONTE VISTA ST
Pasadena, CA 91107
(714) 272-1055
✔ PECOS✔ Accepts Medicare6.1 mi
Rebecca Boyer, MD
Emergency Medicine
NPI 1235691999
300 W HUNTINGTON DR
Arcadia, CA 91007
(626) 898-8000
✔ PECOS✔ Accepts Medicare6.4 mi
Steven Goldberg, MD
Internal Medicine
NPI 1760426464
300 W HUNTINGTON DR
Arcadia, CA 91007
(626) 574-3456
✔ PECOS✔ Accepts Medicare6.5 mi
Collin Hickey, DO
Emergency Medicine
NPI 1235767401
1011 BALDWIN PARK BLVD
Baldwin Park, CA 91706
(833) 574-2273
✔ PECOS✔ Accepts Medicare7.9 mi
Frank Figueroa, N.P.
Nurse Practitioner
NPI 1881986057
2949 LONDON ST
Los Angeles, CA 90026
(909) 800-3426
✔ PECOS✔ Accepts Medicare8.8 mi
Lauralie Johnson, ACNP
Nurse Practitioner
NPI 1033638168
710 S CENTRAL AVE STE 100
Glendale, CA 91204
(818) 660-4490
✔ PECOS✔ Accepts Medicare9.1 mi
Tigran Martikyan, M.D.
Family Practice
NPI 1538425814
325 N KENWOOD ST APT B
Glendale, CA 91206
(818) 433-9915
✔ PECOS9.3 mi
See all 79 clinicians

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Gem Medical Group Corporation's NPI number?

The NPI number for Gem Medical Group Corporation is 1689386815. It was assigned to this organization in the NPPES registry on December 19, 2022. The provider is doing business as GEM Medical Group.

Where is Gem Medical Group Corporation located?

Gem Medical Group Corporation is located at 525 N Garfield Ave, Monterey Park, CA 91754. The listed phone number is (626) 573-2222.

What is Gem Medical Group Corporation's specialty?

The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.

Is Gem Medical Group Corporation enrolled in Medicare?

Yes. Gem Medical Group Corporation is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Gem Medical Group Corporation?

According to the CMS Revalidation Reassignment List (October 2026 release), 79 clinicians in 5 Medicare specialties reassign their Medicare billing to Gem Medical Group Corporation. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. The largest specialties are Emergency Medicine (57), Nurse Practitioner (15) and Family Practice (4). Of these, 4 practice at this address and 25 within 10 miles. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Gem Medical Group Corporation was last updated on March 25, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.