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PLEASANTON EMERGENCY MEDICAL GROUP
NPI 1285625509
Emergency Medicine in Pleasanton, CA

Active since November 04, 2005
5555 W LAS POSITAS BLVD, PLEASANTON, CA 94588(209) 342-2300(209) 524-4240 Get Directions Write a Review

NPPES record last updated: March 4, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Mar 4, 2026, Dec 15, 2025, Nov 24, 2025 and 1 more (4 updates tracked since 2023).

About Pleasanton Emergency Medical Group NPPES

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

PLEASANTON EMERGENCY MEDICAL GROUP (NPI 1285625509) is a healthcare organization registered as an emergency medicine in Pleasanton, California and active in the NPI registry since November 2005. The organization lists Edward Y Kan, Managing Partner, as its authorized official.

NPPES Registry Identity

NPI1285625509
Entity TypeOrganization
Primary Taxonomy207P00000X
Legal Business NamePLEASANTON EMERGENCY MEDICAL GROUP
Location Address5555 W LAS POSITAS BLVDPleasanton, CA 94588
Mailing AddressPo Box 920133Dallas, TX 75392-0143 · (877) 346-2211 · Fax (626) 623-1227
Phone(209) 342-2300
Fax(209) 524-4240
Organization SubpartNo
Authorized OfficialEdward Y KanManaging Partner · (925) 519-2089
Enumeration DateNovember 4, 2005
Last NPPES UpdateMarch 4, 20264 updates tracked since enumeration
NPPES CertifiedMarch 4, 2026
✔ NPI 1285625509 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyEmergency MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207P00000X
License✔ Licensed in CA · 040027
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.
5555 W LAS POSITAS BLVD, Pleasanton, CA 94588
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Other Identifiers 2

OtherZZZ08094ZCA · Blue Shield
MedicaidGR0094321CA

Group Practice 1

Group TaxonomyThis provider is a business group of one or more individual practitioners, who practice with different areas of specialization.193200000X MULTI-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)

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

Clinicians Billing Medicare Through This Organization

50

Medicare enrollment records show 50 clinicians reassign Medicare billing to Pleasanton Emergency Medical Group, which bills Medicare for the services they deliver. Of these, 14 practice at this address and 22 within 10 miles. Listed here are the 20 practicing nearest to this location.

Clinicians by Medicare Specialty 3

Emergency Medicine36
Family Practice7
Nurse Practitioner7

Nearest to this location (20)

See all 50
Michael Costello, MD
Emergency Medicine
NPI 1477544781
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(209) 342-2300
✔ PECOS✔ Accepts MedicareSame address
Colleen Johnson, MD
Emergency Medicine
NPI 1720079049
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(209) 342-2300
✔ PECOS✔ Accepts MedicareSame address
Edward Kan, MD
Emergency Medicine
NPI 1104804426
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(209) 342-2300
✔ PECOS✔ Accepts MedicareSame address
Letitia Li, MD
Emergency Medicine
NPI 1467039511
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(844) 301-0805
✔ PECOS✔ Accepts MedicareSame address
Gerald Nazareno, MD
Emergency Medicine
NPI 1679564983
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(209) 342-2300
✔ PECOS✔ Accepts MedicareSame address
Cynthia Penn Duecker, MD
Emergency Medicine
NPI 1033100359
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(209) 342-2300
✔ PECOSSame address
Nicholas Prewitt, MD
Emergency Medicine
NPI 1992445324
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(844) 301-0805
✔ PECOSSame address
Howard Yoshioka, MD
Emergency Medicine
NPI 1992796221
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(209) 342-2300
✔ PECOSSame address
Stephanie Nguyen, DO
Emergency Medicine
NPI 1427637792
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(925) 847-3000
✔ PECOS✔ Accepts MedicareSame address
Jeremy Estrada
Emergency Medicine
NPI 1841685856
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(925) 416-6585
✔ PECOS✔ Accepts MedicareSame address
Alan Ly, DO
Emergency Medicine
NPI 1972008191
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(415) 990-3017
✔ PECOS✔ Accepts MedicareSame address
Andreas Tjoe, M.D.
Emergency Medicine
NPI 1689818940
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(925) 416-6585
✔ PECOS✔ Accepts MedicareSame address
Douglas Yoshida, MD
Emergency Medicine
NPI 1205817368
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(209) 342-2300
✔ PECOS✔ Accepts MedicareSame address
Yen Hua Yu, D.O.
Emergency Medicine
NPI 1134356868
5555 W LAS POSITAS BLVD
Pleasanton, CA 94588
(925) 416-6585
✔ PECOS✔ Accepts MedicareSame address
Tamara Reni, FNP-C
Nurse Practitioner
NPI 1417731514
4000 DUBLIN BLVD STE 150
Dublin, CA 94568
(925) 479-3773
✔ PECOS✔ Accepts Medicare0.9 mi
Kiranjeet Loewen, D.O.
Family Practice
NPI 1174887947
4050 DUBLIN BLVD
Dublin, CA 94568
(925) 875-3700
✔ PECOS✔ Accepts Medicare0.9 mi
Ann Miller, MD
Family Practice
NPI 1972655090
4050 DUBLIN BLVD
Dublin, CA 94568
(925) 946-1607
✔ PECOS0.9 mi
Yanxia Li, NP
Nurse Practitioner
NPI 1558880062
300 NEAL ST
Pleasanton, CA 94566
(925) 462-2400
✔ PECOS✔ Accepts Medicare2.4 mi
Tsung Wong, MD
Family Practice
NPI 1073513156
87 FENTON ST STE 210
Livermore, CA 94550
(925) 371-8885
✔ PECOS✔ Accepts Medicare5.4 mi
Kelly Morrill, MSN, RN, FNP-BC, CEN
Nurse Practitioner
NPI 1265886071
1133 E STANLEY BLVD
Livermore, CA 94550
(925) 373-4500
✔ PECOS✔ Accepts Medicare5.6 mi
See all 50 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 Pleasanton Emergency Medical Group's NPI number?

The NPI number for Pleasanton Emergency Medical Group is 1285625509. It was assigned to this organization in the NPPES registry on November 4, 2005.

Where is Pleasanton Emergency Medical Group located?

Pleasanton Emergency Medical Group is located at 5555 W Las Positas Blvd, Pleasanton, CA 94588. The listed phone number is (209) 342-2300.

What is Pleasanton Emergency Medical Group's specialty?

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

Is Pleasanton Emergency Medical Group enrolled in Medicare?

Yes. Pleasanton Emergency Medical Group is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Pleasanton Emergency Medical Group?

According to the CMS Revalidation Reassignment List (October 2026 release), 50 clinicians in 3 Medicare specialties reassign their Medicare billing to Pleasanton Emergency Medical Group. 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 (36), Family Practice (7) and Nurse Practitioner (7). Of these, 14 practice at this address and 22 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 Pleasanton Emergency Medical Group was last updated on March 4, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 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.