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Internal Medicine Doctors in California

Data updated monthly · Last refresh October 2026

17,715 Internal Medicine providers practice in California, including 4,245 (24%) offering telehealth. The largest concentration is in Los Angeles. Profiles include federal Open Payments records of money received from drug and device companies in 2025. Listings are drawn from federal public records and are not endorsements.

17,715providers
4,245telehealth
Los Angelestop city

Internal Medicine by city in California

Choose a city to see providers there.

Internal Medicine in Los Angeles1,417 providers
Internal Medicine in San Francisco1,322 providers
Internal Medicine in San Diego970 providers
Internal Medicine in Sacramento602 providers
Internal Medicine in Oakland434 providers
Internal Medicine in San Jose433 providers
Internal Medicine in Stanford383 providers
Internal Medicine in Fresno339 providers
Internal Medicine in Torrance230 providers
Internal Medicine in Long Beach225 providers
Internal Medicine in Bakersfield210 providers
Internal Medicine in Loma Linda209 providers
Internal Medicine in Palo Alto189 providers
Internal Medicine in Anaheim188 providers
Internal Medicine in Orange188 providers
Internal Medicine in Riverside188 providers
Internal Medicine in Walnut Creek184 providers
Internal Medicine in Santa Monica170 providers
Internal Medicine in La Jolla161 providers
Internal Medicine in Roseville159 providers
Internal Medicine in Irvine155 providers
Internal Medicine in Beverly Hills152 providers
Internal Medicine in Santa Clara142 providers
Internal Medicine in Pasadena138 providers

Internal Medicine providers in California

Listed by city, largest first. Payment figures come from the federal Open Payments program, which requires drug and device companies to report what they pay physicians for consulting, speaking, meals, travel and royalties. A disclosed payment is a financial relationship, not evidence of wrongdoing, and many totals reflect a single meal. Figures cover calendar year 2025.

Dr. Stephen Lau
San Leandro, CA · No drug or device payments recorded (2025) · (510) 396-4962
Dr. Tram Nguyen, M.D.
San Leandro, CA · No drug or device payments recorded (2025) · (510) 454-1000
Dr. Tyrone Snipes, D.O.
San Leandro, CA · No drug or device payments recorded (2025) · (510) 969-4253
Dr. Vijay Tiwari, M.D.
San Leandro, CA · No drug or device payments recorded (2025) · (510) 454-1000
Dr. Vincent Wong, D.O.
San Leandro, CA · No drug or device payments recorded (2025) · (510) 454-1000
Dr. Vladimir Titov, MD PHD
San Leandro, CA · $1,594 in drug and device payments (2025) · Telehealth · (510) 351-1193
Dr. Xiaonan Xuan, M.D.
San Leandro, CA · No drug or device payments recorded (2025) · (510) 454-1000
Dr. Young Choi, D.O.
San Leandro, CA · No drug or device payments recorded (2025) · Telehealth · (510) 454-1000
Dr. Anjeet Saini, M.D.
San Luis Obispo, CA · $296 in drug and device payments (2025) · (805) 543-4043
Dr. Ardeshir Talieh, MD
San Luis Obispo, CA · $2,239 in drug and device payments (2025) · (805) 540-5035
Dr. Armando Siqueiros, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 549-5277
Dr. Barbara Bailey, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 801-8830
Dr. Bruce Faecher, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 547-7900
Dr. Camilo Guiang, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 544-1885
Dr. David Javitz, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 543-4043
Dr. David Ralston, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 756-1211
Dr. Deborah Cherry, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · Telehealth · (805) 439-1381
Dr. Divya Manohara
San Luis Obispo, CA · $1,128 in drug and device payments (2025) · (805) 369-8860
Dr. Elliot Klaw, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 541-1177
Dr. Frank Collie, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 543-8310
Dr. Gayle Cekada, M.D
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 903-1391
Dr. Grace Crittenden, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 543-4043
Dr. Ihab Ibrahim, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · Telehealth · (805) 269-1500
Dr. Jana Hanson, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 594-1240
Dr. Jeffrey Bloom, MD
San Luis Obispo, CA · $47 in drug and device payments (2025) · Telehealth · (805) 541-2300
Dr. John Massaro, DO
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 549-0677
Dr. Karen Fong, MD
San Luis Obispo, CA · $162 in drug and device payments (2025) · (805) 242-4455
Dr. Leslie Michel, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 594-1240
Dr. Luke Moselle, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 546-7600
Dr. Marilyn Mcgowan, MD
San Luis Obispo, CA · $84 in drug and device payments (2025) · Telehealth · (805) 549-8023
Dr. Mark Donaldson, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 543-1233
Dr. Mark Soll, M.D
San Luis Obispo, CA · $774 in drug and device payments (2025) · Telehealth · (805) 549-9555
Dr. Mark Stilphen, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 543-4043
Dr. Maureen Haas, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 269-1500
Dr. Michael Steele, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 543-4347
Dr. Philip Borgardt, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 540-5544
Dr. Philippe Duhaime, M.D
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 546-7000
Dr. Phoebe Chen, M.D.
San Luis Obispo, CA · $70 in drug and device payments (2025) · Telehealth · (805) 549-8023
Dr. Reetika Kumar, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (800) 547-7900
Dr. Robert Brenman, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 541-1177
Dr. Robert Misson, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 547-7900
Dr. Samer Othman, MD
San Luis Obispo, CA · $355 in drug and device payments (2025) · Telehealth · (805) 544-7246
Dr. Sowmya Oza, M.D.
San Luis Obispo, CA · $40 in drug and device payments (2025) · Telehealth · (805) 597-6715
Dr. Stephen Hansen, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 544-2737
Dr. Stephen Hilty, M.D.
San Luis Obispo, CA · No drug or device payments recorded (2025) · Telehealth · (805) 543-8310
Dr. Surya-rao Pakalapati, MD
San Luis Obispo, CA · No drug or device payments recorded (2025) · (805) 543-1233
Dr. Thomas Nguyen, MD
San Luis Obispo, CA · $40 in drug and device payments (2025) · Telehealth · (805) 549-8023
Dr. Arturo Tolentino, M.D.
San Marcos, CA · $78 in drug and device payments (2025) · (833) 867-4642
Dr. Francisco Marquez, M.D.
San Marcos, CA · No drug or device payments recorded (2025) · (760) 510-4313
Dr. Izabela Witczak, M.D
San Marcos, CA · $43 in drug and device payments (2025) · (760) 736-6700

Conditions Internal Medicine providers in California commonly treat

Patients often search by condition rather than specialty. These are conditions typically managed by Internal Medicine providers. Individual practices vary, so confirm with the provider before booking.

Common questions

How many Internal Medicine providers are in California?

There are 17,715 Internal Medicine providers with active NPI records practicing in California, according to federal NPPES data refreshed monthly.

Do Internal Medicine providers in California offer telehealth?

Yes. 4,245 of the 17,715 Internal Medicine providers in California (about 24%) report offering telehealth services in CMS data.

Which cities in California have the most Internal Medicine providers?

Los Angeles (1,417), San Francisco (1,322), San Diego (970) have the highest concentration of Internal Medicine providers in California.

How many Internal Medicine providers in California received drug or device company payments?

5,614 of 17,715 Internal Medicine providers in California (32%) received at least one payment from a drug or device company in 2025, according to the federal Open Payments program.

What conditions do Internal Medicine providers in California treat?

Internal Medicine providers commonly treat high blood pressure, type 2 diabetes, high cholesterol, preventive care, chronic disease management and related conditions. Individual practices vary, so confirm with the provider before booking.

Where does this data come from?

Provider counts and profiles come from the federal NPPES registry and CMS Doctors and Clinicians files. Payment figures come from the CMS Open Payments program for calendar year 2025. The directory refreshes monthly.

Do most Internal Medicine Doctors in California work in independent practices or large health systems?

Among 10,847 Internal Medicine Doctors in California enrolled in Medicare, 20% bill through a solo or small practice with fewer than 10 clinicians, 12% through a mid-size group of 10 to 99, and 67% through a large group or health system with 100 or more clinicians, according to CMS enrollment records.

Which hospitals do Internal Medicine Doctors in California work at?

According to CMS facility affiliation records, the California hospitals where the most Internal Medicine Doctors hold privileges are Stanford Health Care in Stanford; UCSF Medical Center in San Francisco; Ronald Reagan UCLA Medical Center in Los Angeles.

Related reading on HealthcareDiscovery.AI

Internal Medicine in all 50 states Search all 17,715 in the directory Ask Zach for help choosing

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Try a city like Tucson, a zip like 85016, or a specialty like psychiatry. For a doctor by name, use the full search.
Sources: NPPES (CMS), Doctors and Clinicians national files, CMS Open Payments 2025. Updated monthly. Records are public federal data and are not verified credentials, licensure checks, or endorsements. This directory is informational and not medical advice. How we build this directory. Are you a Internal Medicine in California? Get featured.