The Oregon Clinic Gastroenterology South Tualatin Oregon Location

Gastroenterology South – Tualatin

19250 SW 90th Ave
Tualatin, OR 97062
M-F: 6:15am - 5:00pm
Phones answered M-F: 8:00am - 4:45pm
TEL: 503-692-3750
FAX: 503-691-2324

At The Oregon Clinic Gastroenterology South, we strive to make your visit with us as quick and caring as possible. Each step along the way through your treatment, you can count on fine, personalized outpatient care from our specialized and highly skilled medical, nursing, and support staff.

In addition to diagnosing and treating problems, we also provide prevention and early detection procedures, including endoscopy, which uses narrow, flexible lighted tubes with built-in video cameras to inspect the inside of the intestinal tract. Our physicians are specially trained to perform colonoscopies (scope of the large intestine), upper endoscopies (scope of the esophagus, stomach, and duodenum), endoscopic ultrasounds, and other sophisticated endoscopic procedures.

Once you have your appointment, please arrive at least 15 minutes early, and bring your referral forms (if required), insurance information and co-payments. We will automatically request your medical information from your primary care provider before your visit. When you schedule, please let us know if you’ve had any relevant x-rays, ultrasounds, or other imaging studies.

Medical emergencies may cause unexpected delays in our schedule. Your patience and understanding are appreciated. If you must cancel or reschedule your appointment, please call us as soon as possible.

The Oregon Clinic Gastroenterology South – Tualatin earned 3rd place in the America’s Best Ambulatory Surgery Centers – Oregon 2024 ranking by Newsweek. Learn more here.

Since November 2014, each of our three gastroenterology groups has been participating in the GI Quality Improvement Consortium (GIQuIC) program. Being part of this organization requires a focus on enhancing patient care through real-time peer-based performance evaluation. Click to read more on the GIQuIC website.

GI South has been recognized by the American Society for Gastrointestinal Endoscopy for promoting quality in endoscopy. Congratulations to such a hard-working team!

Endoscopy Center Ownership

  • Paul Anderson, MD
  • Brian Applebaum, MD
  • Michelle Beilstein, MD
  • Mark Cahill, MD
  • C.Y. Michael Chang, MD
  • Stephen Chen, MD
  • Ryan Childers, MD
  • Jeffrey Douglass, MD
  • Jeffrey Duman, MD
  • Sarah Lee, MD
  • Ronald Lew, MD
  • Nima Motamedi, MD
  • Monina Pascua, MD
  • Swapna Reddy, MD
  • Erik Van Kleek, MD
  • Zibing Woodward, MD

Mission Statement

Our mission is to be the highest quality provider of digestive disease services and to continually explore and exceed the needs of our patients and referring providers.

Core Values

Excellence: We strive to provide the highest quality care in a manner that is evidence-based and innovative.
Compassion: Every member of our team endeavors to provide care with empathy and mutual respect to our patients’ needs.
Teamwork: All members of our staff collaborate and work together to care for our patients.
Community:  We are committed to serve the greater community of our referring providers and patients.


The Oregon Clinic Gastroenterology South Building
19250 SW 90th Ave
Tualatin, OR 97062


  • From SW 90th Ave, turn into driveway across from Kaiser
  • Turn right into clinic parking lot

Learn more about Gastroenterology at The Oregon Clinic