About MacArthur Gastroenterology

Compassionate, Preventive Care for the Bay Area

For more than 40 years, Dr. Ralph L. Peterson and the MacArthur Gastroenterology team have brought a preventive, whole person approach to digestive and liver health care in Oakland.

Meet Your Physician

Dr. Ralph L. Peterson, MD

Medical Director, MacArthur Gastroenterology

Dr. Ralph L. Peterson brings more than 40 years of medical experience to MacArthur Gastroenterology, including over 30 years focused on gastroenterology and internal medicine. For more than a decade, he has treated viral hepatitis with a cure rate above 90 percent in Hepatitis B and C cases, and he continues to champion a preventive medicine approach to liver and digestive health.

Dr. Peterson serves as Medical Director for UFirst Health Partners, a nonprofit dedicated to fatty liver disease awareness, and sits on advisory boards for major pharmaceutical companies including Gilead. His work has been recognized by the American Cancer Society, the 100 Black Men of America Bay Area chapter, and the Alameda County Board of Supervisors for outstanding service in men’s health.

Outside the clinic, Dr. Peterson has served as an international medical volunteer in Sierra Leone and the Philippines, and holds a Masters Track and Field world record in the 4×100 relay.

Recognition & Awards

A Legacy of Leadership and Service

Leadership & Advisory

Advisory boards for major pharmaceutical companies, including Gilead. Medical Director, UFirst Health Partners, a 501(c)(3) nonprofit for fatty liver disease awareness. Head of R&D, NEXT2ME, LLC-1440. Inventor, 1440 Vibrational Energetic Spray Supplements.

Community & Professional Recognition

Recognized by the American Cancer Society, 100 Black Men of America, and 100 Black Men of the Bay Area. Honored by the Alameda County Board of Supervisors for Outstanding Service in Men’s Health.

Global & Athletic Service

Medical Team Leader for a national medical needs assessment in Sierra Leone. Volunteer physician in Bohol, Philippines, training local providers in GI and Hepatitis B/C treatment. Masters Track and Field World Record holder, 4×100 relay.

2007

Began HCV testing to raise awareness and connect at risk patients to care.

2013

MacArthur Gastroenterology began HCV treatment.

First in Alameda County

Approved to prescribe the first single pill, once daily complete Hepatitis C treatment.

A Pioneer in Hepatitis C Care

Advancing Treatment Access in Alameda County

Dr. Peterson began offering Hepatitis C testing in 2007 to raise awareness and connect at risk patients with care. In 2013, MacArthur Gastroenterology began treating Hepatitis C directly. He was the first physician in Alameda County approved to prescribe the first single pill, once daily complete Hepatitis C treatment, bringing a simpler, more effective path to a cure within reach for local patients.

Patient Education

What Is Gastroenterology?

Gastroenterology is the branch of medicine focused on the digestive system, from the esophagus and stomach to the liver, colon, and beyond. A gastroenterologist is a physician who completes years of additional training beyond medical school specifically to diagnose and treat these conditions.

Dr. Peterson brings that depth of training together with a preventive, whole person approach, so problems are caught early and treated with a clear plan, not just a prescription.

Our Clinic

A Welcoming Place for Digestive and Liver Health

MacArthur Gastroenterology is a full service digestive health clinic in Oakland, California, offering a calm, welcoming environment for every visit. Our team combines modern diagnostic technology with a personal, unhurried approach to care, so you always feel heard and understood.

Comprehensive digestive and liver care under one roof
Multilingual care team: English, Spanish, Vietnamese, Cantonese, Mandarin, Tagalog, and Arabic
Convenient Oakland location at 10520 MacArthur Blvd.
A preventive, patient centered approach to care

In Their Words

Patient and Colleague Testimonials

I appreciate the quality of professional care that my patients receive from Dr. Peterson and his highly qualified staff.

Dr. H. Geoffrey Watson, Watson Wellness Center, Oakland, CA

I like his professionalism and genuine care with my GI problems. I appreciate his willingness to help me. I feel much better with the treatment I received from Dr. Peterson.

Lorena Rodriguez, Loan Officer, Oakland, CA

More patient stories coming soon.

Our Services

Two Ways We Help You Stay Ahead of Liver and Metabolic Health

Fatty Liver Screening

A quick, non-invasive Velacur scan detects fatty liver disease and liver stiffness in minutes, with no needles and no prep required.

Weight Management

Physician supervised programs, including GLP-1 therapy when appropriate, designed around your metabolic health and monitored by our clinical team.

For Referring Physicians

See Your Primary Care Physician for a Referral

MacArthur Gastroenterology accepts new patients by physician referral. If you are experiencing digestive or liver related symptoms, ask your primary care physician for a referral to our office, and our team will take it from there.

What Your Referring Physician Should Send

Relevant lab work
Medications and progress notes
Insurance information
Phone and fax number for the referring physician’s office

Ready to take the next step in your health?

Ask your primary care physician for a referral, or call our office and we will help guide you through next steps.