Southern California's

Premier Gastroenterology Practice

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Welcome to

United Gastroenterologists

The mission of United Gastroenterologists is to improve the health of our community by setting the standard of excellence in patient care.

Specifically we aim:

  • To provide the highest quality compassionate care and service for all people in the prevention, diagnosis, and treatment of digestive diseases.
  • To attract a team of physicians and other health care professionals of the highest moral character and greatest skill.
  • To be the premier Gastroenterology practice in our region with a dedication to achieving the highest levels of patient satisfaction while implementing continued process improvement.
  • To provide our patients access to advanced cutting-edge Gastroenterology services by leveraging our group’s resources and close relationships and affiliations with University medical centers in the region.
  • To demonstrate empathy in caring for patients which is more than just physical healing – it’s establishing a connection and trusting relationship with care that encompasses mind, body, and spirit.

Our History

Dr. Thomas Eastman began a solo Gastroenterology private practice based in Fallbrook, CA over 25 years ago. In 2002, Dr. John Hong joined Dr. Thomas Eastman. The decision was made to establish an independent private practice medical corporation (United Gastroenterologists). The practice started out with just three employees, two physicians, and one desktop computer serving the communities of Fallbrook and Temecula. From its inception, UG has been committed to providing the highest level of quality care by serving our patients with the utmost compassion.

Over the years UG has continued to expand tremendously as a regional GI referral practice for Riverside County, San Diego County and Orange County.   In 2005, the practice opened up United Surgery Center-Murrieta, a state licensed, Medicare certified, AAAHC (Accreditation Association for Ambulatory Health Care) Ambulatory Surgery Center. Over 100,000 procedures have been successfully performed since.  Since then, additional Ambulatory Surgery Centers:  United Surgery Center-Temecula, United Surgery Center-Irvine, United Surgery Center-Orange and United Surgery Center – Encinitas have been added.

Over the years the practice has added over two dozen specialties, becoming one of Southern California’s premier multi-specialty practices. These specialties include but are not limited to: the GI Imaging Center (CT Enterography, CT Colonography, Ultrasound) accredited by the American College of Radiology, the Center for Medical Weight Loss, an Anatomic Pathology Lab accredited by The Joint Commission (National Quality Approval Award), a fully integrated Clinical Research Institute, Urology, ENT, Audiology and more. United Gastroenterologists has over nearly 100 clinical providers who are committed to providing excellent high quality patient care to the residents in the Southern California counties of Riverside, Orange, San Diego and Los Angeles.

COVID-19 Guide

View the measures we’re taking to ensure your health & safety are top priority.

Our Locations

We proudly serve the counties of Riverside, Orange, San Diego and Los Angeles. View our locations and specialties below to find a specialist near you.

Schedule an Appointment

Scheduling an appointment is simple. We are proud to offer multiple ways to receive care safely, including Telemedicine visits.

Hospital Relationships

United Gi Affiliation Logos
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