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Internal Medicine Providers in Los Altos, CA

Browse 29 Internal Medicine providers listed in NPPES with a practice address in Los Altos, California.

29 Healthcare Providers

How Los Altos compares with the U.S.

Los Altos has 94 clinicians in Internal Medicine per 100,000 residents, 2.1 times the U.S. rate of 44.

That is 29 active clinicians in Internal Medicine with a practice address in Los Altos, for a population of 30,698.

The California rate is 45 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.

88% of clinicians in Internal Medicine in Los Altos listed in the CMS Medicare file (14 of 16) accept Medicare assignment. That is lower than the California share of 96%.

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.

88% of clinicians in Internal Medicine in Los Altos listed in the CMS Medicare file (14 of 16) have a CMS telehealth indicator, meaning their recent Medicare claims include telehealth services. That is higher than the California share of 38%.

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).

Internal Medicine Medicare (PECOS) Enrollment & Ordering Eligibility

Medicare enrollment and order/referring eligibility listed by CMS for Internal Medicine practitioners in Los Altos, CA

Source: CMS PECOS
PECOS Enrolled Specialists 17 In Los Altos, CA
Part B Lab & Imaging Eligible 23 Diagnostic Referrals
DME Ordering Eligible 25 Durable Medical Equipment
Home Health Agency Referrals 23 HHA Ordering Eligible
Showing 1โ€“20 of 29 providers
With recent CMS data first, then Aโ€“Z

Dr. Tinuola Oluwasola Ademola , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
370 Distel Cir, Los Altos, CA 940221404
Phone: 6502545200
NPI Identifier 1437472974
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Dr. Bhanu-Rekha Bhaskar , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
370 Distel Cir, Los Altos, CA 940221404
Phone: 6502545200
NPI Identifier 1932273539
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Dr. Jacqueline Denkabe , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
371 Distel Circle, Los Altos, CA 940229402
Phone: 6502545200
NPI Identifier 1194883520
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Dr. Jessica Barry Favreau , MD

Internal Medicine

Active NPI Status
1 1st St Ste 15, Los Altos, CA 940222756
Phone: 6506682558
NPI Identifier 1841450731
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Dr. Julia Fong , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
370 Distel Cir, Los Altos, CA 940221404
Phone: 6502545200
NPI Identifier 1154409746
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Dr. Simon Anthony Humphries , MD

Internal Medicine

Active NPI Status Telehealth Services Available
811 Altos Oaks Dr, Suite 2, Los Altos, CA 940245426
Phone: 6509176920
NPI Identifier 1023149440
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Dr. Francis Lastufka , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
370 Distel Circle, Los Altos, CA 940221404
Phone: 6502545200
NPI Identifier 1144312141
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Dr. Ronda Macchello , MD

Internal Medicine

Active NPI Status
370 Disel Cir, Los Altos, CA 95022
Phone: 6502545200
NPI Identifier 1114019742
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Dr. Janusz J Madej , MD

Internal Medicine

Active NPI Status
339 S San Antonio Rd Ste 1a, Los Altos, CA 940223699
Phone: 6505291669
NPI Identifier 1376616706
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Dr. Jessica Madej , MD

Internal Medicine

Active NPI Status
339 S San Antonio Rd Ste 1a, Los Altos, CA 940223699
Phone: 6505291669
NPI Identifier 1417537218
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Payvand Milani

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
370 Distel Cir, Los Altos, CA 940221404
Phone: 6502545200
NPI Identifier 1548647126
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Dr. Carrie Riopel Mousseau , MD

Internal Medicine

Active NPI Status
895 Sherwood Ave Ste 100, Los Altos, CA 940221344
Phone: 6508885790
NPI Identifier 1447387451
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Dr. Lailey Naomi Oliva , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
370 Distel Cir, Los Altos, CA 940221404
Phone: 6502545200
NPI Identifier 1073768727
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Dr. Gina Serraiocco , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
370 Distel Cir, Los Altos, CA 940221404
Phone: 6502545200
NPI Identifier 1063504553
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Dr. Patricia Roukee Sitnitsky , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
827 Altos Oaks Dr Ste 4, Los Altos, CA 940245490
Phone: 4084955770
NPI Identifier 1790896231
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Dr. Susan Krieger Sorensen , MD

Internal Medicine

Active NPI Status
851 Fremont Ave, Suite 102, Los Altos, CA 940245698
Phone: 6509415028
NPI Identifier 1366523862
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Dr. Dianne Storey , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
370 Distel Cir, Los Altos, CA 940221404
Phone: 6502545200
NPI Identifier 1740372259
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Dr. Karen Jill Suskiewicz , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
370 Distel Circle, Pamf, Los Altos, CA 94022
Phone: 6502545200
NPI Identifier 1770508533
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Dr. Paul Tang , MD

Internal Medicine

Active NPI Status Accepts Medicare Assignment
370 Distel Circle, Los Altos, CA 940221404
Phone: 6502545200
NPI Identifier 1043327737
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Dr. Karthikeyan Viswanathan , DO

Internal Medicine

Active NPI Status
4546 El Camino Real Ste B7, Los Altos, CA 940221069
Phone: 8663624246
NPI Identifier 1396128336
View Full Profile

Frequently Asked Questions about Internal Medicine in Los Altos

How do I check a Internal 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.

Other Specialties in Los Altos

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