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Emergency Medicine Providers in Pleasanton, CA

Browse 27 Emergency Medicine providers listed in NPPES with a practice address in Pleasanton, California.

27 Healthcare Providers

How Pleasanton compares with the U.S.

Pleasanton has 35 clinicians in Emergency Medicine per 100,000 residents, about 1.7 times the U.S. rate of 21.

That is 27 active clinicians in Emergency Medicine with a practice address in Pleasanton, for a population of 76,960.

The California rate is 20 per 100,000 residents.

What these numbers mean

Clinicians per 100,000 residents compares places of different sizes. We count active clinicians who list a practice address in the area in the federal NPI registry (NPPES) and divide by the number of people who live there, according to the U.S. Census Bureau. The U.S. rate is the same calculation for the whole country.

A higher number does not mean it is easier to get an appointment, that wait times are shorter, or that care is better. It also does not show how many clinicians are accepting new patients or which insurance plans they take. A lower number does not by itself mean there is a shortage.

City counts use the city name in each clinician's practice address. That postal city can cover a larger or smaller area than the city limits the Census Bureau uses for population, and many clinicians list only one address even if they work in several places. Cities with hospitals or large medical centers often list more specialists than the number of residents alone would suggest, because patients also come from nearby areas.

92% of clinicians in Emergency Medicine in Pleasanton listed in the CMS Medicare file (12 of 13) accept Medicare assignment. That is similar to the California share of 97%.

Only 13 of 27 active clinicians in Emergency Medicine in Pleasanton appear in the CMS Medicare file, so this share describes that smaller group.

What is Medicare assignment?

A clinician who accepts Medicare assignment agrees to take the Medicare-approved amount as full payment for services that Original Medicare covers. You usually still pay your deductible and coinsurance. This comes from the CMS Doctors and Clinicians file and applies to Original Medicare only. Medicare Advantage plans have their own provider networks. It does not show whether a clinician is taking new patients.

Some clinicians are listed as "may accept assignment," which means they can decide case by case. Clinicians without an assignment flag, or who are not in the CMS file, are not counted as accepting assignment. That does not mean they refuse Medicare. Ask the office before your visit.

None of the 13 clinicians in Emergency Medicine in Pleasanton listed in the CMS Medicare file have a CMS telehealth indicator. Some may still offer telehealth; ask the office.

About the telehealth indicator

The telehealth indicator comes from CMS. It marks clinicians whose recent paid Medicare claims include services delivered by telehealth. It means a clinician has provided some services by telehealth, not that every visit can be done online. A clinician without the indicator may still offer telehealth, for example to patients who are not on Medicare. Ask the office which visits can be done by video or phone.

These figures summarize public federal data. They do not measure quality of care, appointment availability, or whether a clinician accepts your insurance or new patients. Registry addresses can be out of date. Please confirm details directly with the office and your plan. This information is not medical advice.

Prepared by T-MedInfo from NPPES, CMS and U.S. Census Bureau data. Questions or corrections: support@true-medinfo.com ยท Methodology

Sources: Clinician counts and practice addresses: NPPES NPI Registry, Centers for Medicare & Medicaid Services (CMS), data as of August 2026. Medicare assignment and telehealth indicators: CMS Doctors and Clinicians National Downloadable File. Population: U.S. Census Bureau, American Community Survey 2020-2024 5-Year Estimates, Table B01003 (Total Population).

Emergency Medicine Medicare (PECOS) Enrollment & Ordering Eligibility

Medicare enrollment and order/referring eligibility listed by CMS for Emergency Medicine practitioners in Pleasanton, CA

Source: CMS PECOS
PECOS Enrolled Specialists 19 In Pleasanton, CA
Part B Lab & Imaging Eligible 19 Diagnostic Referrals
DME Ordering Eligible 20 Durable Medical Equipment
Home Health Agency Referrals 19 HHA Ordering Eligible
Showing 1โ€“20 of 27 providers
With recent CMS data first, then Aโ€“Z

Dr. Dennis Keith Alfaro , MD

Emergency Medicine

Active NPI Status
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1407847718
View Full Profile

Dr. James E. Burgess , MD

Emergency Medicine

Active NPI Status
7601 Stoneridge Dr, Pleasanton, CA 945884501
Phone: 9258475000
NPI Identifier 1467530568
View Full Profile

Dr. Michael John Costello , MD

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1477544781
View Full Profile

Jeremy Estrada

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 9254166585
NPI Identifier 1841685856
View Full Profile

Dr. Colleen Ann Johnson , MD

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1720079049
View Full Profile

Dr. Edward Y Kan , MD

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1104804426
View Full Profile

Dr. Robert T. Kwak , MD

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
Po Box 702, Pleasanton, CA 945660070
Phone: 6507996666
NPI Identifier 1588963243
View Full Profile

Dr. Alan Albert Ly , DO

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 4159903017
NPI Identifier 1972008191
View Full Profile

Dr. Candice P. Mcneil , MD

Emergency Medicine

Active NPI Status
5000 Hopyard Rd, Suite 100, Pleasanton, CA 945883348
Phone: 8006177717
NPI Identifier 1801097241
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Dr. Gerald Roy Nazareno , MD

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1679564983
View Full Profile

Dr. Stephanie Nguyen , DO

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 9258473000
NPI Identifier 1427637792
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Dr. Cynthia Sue Penn-Duecker , MD

Emergency Medicine

Active NPI Status
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1033100359
View Full Profile

Dr. Nicholas Prewitt , MD

Emergency Medicine

Active NPI Status
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 8443010805
NPI Identifier 1992445324
View Full Profile

Dr. Christopher Clark Severson , MD

Emergency Medicine

Active NPI Status
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1750365516
View Full Profile

Dr. Andreas Tjoe , MD

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 9254166585
NPI Identifier 1689818940
View Full Profile

Dr. Douglas Kei Yoshida , MD

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1205817368
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Dr. Howard Daniel Yoshioka , MD

Emergency Medicine

Active NPI Status
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1992796221
View Full Profile

Dr. Yen-Hua Yu , DO

Emergency Medicine

Active NPI Status Accepts Medicare Assignment
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 9254166585
NPI Identifier 1134356868
View Full Profile

Dr. Richard D. Carvolth , MD

Emergency Medicine

Active NPI Status
5000 Hopyard Rd, Suite 100, Pleasanton, CA 945883348
Phone: 9259241600
NPI Identifier 1932159829
View Full Profile

Dr. Paul David Chasin , MD

Emergency Medicine

Active NPI Status
5555 W Las Positas Blvd, Pleasanton, CA 945884000
Phone: 2093422300
NPI Identifier 1649261959
View Full Profile

Frequently Asked Questions about Emergency Medicine in Pleasanton

How do I check a Emergency Medicine practitioner's license?

Each practitioner profile shows the NUCC taxonomy code and any state license number the practitioner reported to NPPES, plus a link to the California licensing board lookup. NPPES entries are self-reported; current license status is published only by the state board.

Why is a practitioner missing from this list?

This list shows NPI records that are active in NPPES. A deactivated NPI keeps its profile with the deactivation date and practice history; find it with the site search by name or NPI number.