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Due to inclement weather, all GSI Offices and Endoscopy Centers will be closed on Monday, 1/26/2026. 

We will be opening at 11am on Tuesday, 1/27/2026. Outpatient procedures and office appointments scheduled before 11am are being rescheduled. Please call our office at 804-285-8206 to schedule or reschedule your appointment as needed.

San Antonio Gastroenterology Associates: San Antonio -Stone Oak – Sonterra

San Antonio Gastroenterology Associates: San Antonio -Stone Oak – Sonterra

Monday – Thursday
8:00AM – 5:00PM

Friday
8:00AM – 4:00PM

Request An Appointment

Request An Appointment

If you are experiencing a medical emergency, please call 9-1-1. This form is intended for non-urgent appointment requests only. Our office will handle non-emergency requests within 48 hours.

San Antonio Gastroenterology Associates: San Antonio -Stone Oak – Sonterra
150 East Sonterra Boulevard, Suite 100, San Antonio, TX 78258
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Our Providers

Joseph E. Johnson IV, M.D.

Gastroenterologist
 in San Antonio, TX
Meet Dr. Johnson

Chaithanya Mallikarjun, M.D.

Gastroenterologist
 in San Antonio, TX
Meet Dr. Mallikarjun

Request An Appointment

If you are experiencing a medical emergency, please call 9-1-1. This form is intended for non-urgent appointment requests only. Our office will handle non-emergency requests within 48 hours.