HealthcareDiscovery.AI / Doctors / California / San Marcos / Internal Medicine

Internal Medicine in San Marcos, California

Data updated monthly · Last refresh September 2026

17 Internal Medicine providers practice in San Marcos. Listings are drawn from federal public records and are not endorsements.

Internal Medicine providers in San Marcos

Listed alphabetically. 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. 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
Dr. Joseph Czvik, MD
San Marcos, CA · $356 in drug and device payments (2025) · (760) 471-1020
Dr. Justin Charles, MD
San Marcos, CA · $567 in drug and device payments (2025) · Telehealth · (442) 372-2330
Dr. Kathryn Germeraad, DO
San Marcos, CA · No drug or device payments recorded (2025) · Telehealth · (858) 554-1212
Dr. Lauren Clarine, D.O.
San Marcos, CA · No drug or device payments recorded (2025) · (877) 236-0333
Dr. Lauren Jefferis, MD
San Marcos, CA · No drug or device payments recorded (2025) · (760) 736-6700
Dr. Marie Russell, MD.
San Marcos, CA · $141 in drug and device payments (2025) · (760) 736-8689
Dr. Meenu Bawa, M.D
San Marcos, CA · No drug or device payments recorded (2025) · Telehealth · (619) 323-8789
Dr. Minh Nguyen, M.D.
San Marcos, CA · $22 in drug and device payments (2025) · (619) 757-0141
Dr. Mona Arasoghli, M.D.
San Marcos, CA · No drug or device payments recorded (2025) · (800) 290-5000
Dr. Samuel Poniachik, M.D
San Marcos, CA · $546 in drug and device payments (2025) · (760) 736-6700
Dr. Shreya Chandra, MD
San Marcos, CA · No drug or device payments recorded (2025) · (760) 736-6700
Dr. Sze Hoay Ding, M.D.
San Marcos, CA · No drug or device payments recorded (2025) · (619) 318-7476
Dr. Tina Tran, MD
San Marcos, CA · $42 in drug and device payments (2025) · Telehealth · (760) 806-5700
Dr. Tyler Sprague, D.O.
San Marcos, CA · No drug or device payments recorded (2025) · Telehealth · (760) 304-1383

Conditions Internal Medicine providers in San Marcos, 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 San Marcos, California?

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

What conditions do Internal Medicine providers in San Marcos treat?

Internal Medicine providers in San Marcos 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 records 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.

All specialties in San Marcos Internal Medicine across California

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.