Request an Appointment
Your Trusted Partner for Exceptional Gastroenterology Services in San Antonio
Personalized, Around-The-Clock Treatment By Board-Certified Physicians
Your gastroenterology needs are at the forefront when you choose our team at San Antonio Gastroenterology Associates. We’re a network of skilled and experienced GI professionals who are dedicated to getting you connected with the right resources and treatments. Our team looks forward to becoming a trusted source for your GI needs throughout the San Antonio, TX area. Improve your digestive health today and schedule an appointment.
OUR SERVICES
Anorectal Manometry
Argon Laser Therapy
Capsule Endoscopy
Chronic Care Management
Colon Cancer Screening
Colonoscopy
Esophageal Dilation
Esophageal Manometry
Esophagogastroduodenoscopy (EGD)
Feeding Tube Insertion (PEG)
FibroScan®
Flexible Sigmoidoscopy
Hemorrhoid Banding
Infusion Therapy (IV Infusion)
Sphincterotomy
Services
Anorectal Manometry
Argon Laser Therapy
Capsule Endoscopy
Chronic Care Management
Colon Cancer Screening
Colonoscopy
Esophageal Dilation
Esophageal Manometry
Esophagogastroduodenoscopy (EGD)
Feeding Tube Insertion (PEG)
FibroScan®
Flexible Sigmoidoscopy
Hemorrhoid Banding
Infusion Therapy (IV Infusion)
Sphincterotomy
LATEST RESOURCES
When Should You See a Doctor for Hemorrhoids?
At San Antonio Gastroenterology Associates, we regularly encounter patients from San Antonio, TX, who are grappling with the discomfort of hemorrhoids. These swollen veins in the lower rectum or anus can lead to pain, itching, and in some cases, bleeding. Without appropriate treatment, hemorrhoids can progress into more severe health problems. It’s important to recognize
Read MoreReviews
Bravo!!! I had been feeling sick for years now and I was so scared of going to the gastroenterologist because of fear of what they would tell me. I got an appointment next door with Cynthia Guzman which she got me my endoscopy and colonoscopy scheduled up within 7 days of my first ever appointment! I lived the most 7 stressful days of my life because I had never been deep sedated and since I have sleep apnea, I thought I wasn't going to wake up lol. I was pretty much saying goodbye to the world around me lol! Anyways I was the first one on the schedule and trust me, if you can get it early in the morning the better since you can't eat or drink anything until after the procedure. Madeline in the front was so kind! Thank you! We then went to the back where I was getting prepped and reviewed my medical history. Sonia the anesthesiologist kept reassuring me everything was going to be fine and that i'd soon be on my way to eating a good meal. All the nurses, technician, and Dr. Johnson also reassured me not to worry about the process. What felt relaxing was the music they have throughout the clinic.. even in the room where the procedure was lol. I told my wife that helped a lot! I would recommend this to anyone needing to get an endoscopy or colonoscopy. This is a really great place and with incredible staff. I usually get a receipt from other offices when I get seen. This one gave me a get well card signed by the staff. Thank you guys!!!
Dr. Mallikarjun and her Nurse David are phenomenal. These types of appointments/procedures can be very stressful. Their availability, kindness, thoroughness, and transparency made everything run smoothly. Thank you both for taking such excellent care of myself and my husband!
I want to sincerely thank the entire team for the outstanding care I received during my recent colonoscopy. As someone with hearing loss and some anxiety—especially about IVs and undergoing a procedure for the first time—I was truly nervous. But the entire experience went unbelievably smoothly, and I’m incredibly grateful.
Lillie, the RN in the pre-procedure room, was amazing—kind, patient, and very attentive to my hearing needs. She took the time to explain everything clearly, made me feel at ease, and applied the IV so smoothly that it eased a lot of my anxiety.
I also want to recognize Crystal, my anesthesiologist (forgot her name), and her team in the procedure room. They helped me feel comfortable and relaxed, which made a big difference. It was reassuring to see Dr. Mallikarjun before the procedure—she was warm, kind, and took a moment to ask how I was feeling and if I had any questions.
After the procedure, Kenneth, the recovery RN, was so attentive and made sure I was doing well as I woke up. His care and attentiveness were much appreciated.
Dr. Mallikarjun is a truly compassionate and knowledgeable Gastroenterologist. I had the chance to meet her previously during a follow-up for my wife, and I was very impressed by how clearly she explained everything, showing us details on her laptop and walking us through the procedure. Her calm and thoughtful approach really stuck with me, and I felt confident knowing I’d be in her care.
Thanks to this wonderful team, I feel relieved, cared for, and confident about my health moving forward. I couldn’t have asked for a better experience. Five stars all around—and both my wife and I will definitely return for any future care.
Lillie, the RN in the pre-procedure room, was amazing—kind, patient, and very attentive to my hearing needs. She took the time to explain everything clearly, made me feel at ease, and applied the IV so smoothly that it eased a lot of my anxiety.
I also want to recognize Crystal, my anesthesiologist (forgot her name), and her team in the procedure room. They helped me feel comfortable and relaxed, which made a big difference. It was reassuring to see Dr. Mallikarjun before the procedure—she was warm, kind, and took a moment to ask how I was feeling and if I had any questions.
After the procedure, Kenneth, the recovery RN, was so attentive and made sure I was doing well as I woke up. His care and attentiveness were much appreciated.
Dr. Mallikarjun is a truly compassionate and knowledgeable Gastroenterologist. I had the chance to meet her previously during a follow-up for my wife, and I was very impressed by how clearly she explained everything, showing us details on her laptop and walking us through the procedure. Her calm and thoughtful approach really stuck with me, and I felt confident knowing I’d be in her care.
Thanks to this wonderful team, I feel relieved, cared for, and confident about my health moving forward. I couldn’t have asked for a better experience. Five stars all around—and both my wife and I will definitely return for any future care.
The staff is always professional and friendly. The office is airy and clean. The atmosphere is welcoming and warm. Dr. GUERRA is friendly and is unhurried to listen to you the patient. He explains with terms that are easy to comprehend. I had my endo and colonoscopy done at this location. Tip notch... Overall, exceptional...
I have been to Dr Johnson for a Colonoscopy and Endoscopy twice.It has been a fantastic experience and everyone was so nice from beginning to end. Highly recommend!
Dr. Taheri and the whole staff are caring and efficient. They communicate very well and make the patient feel comfortable through the whole process. Highly recommend Dr. Taheri and everyone in his offices!
Great organization quick and efficient.
Great Dr Serna He listens to My concerns of my well being, especially my stomach problems.
Dr. Johnson has been my doctor for about 15 years and I am very pleased. He is a very caring, compassionate doctor and explains everything in detail. Have referred several family members to him.
I had procedure yesterday with Doctor josephE.Johnson .All the nurses, Dr. Johnson, and the anesthesiologist were great. I was very stressed that day, but they explained everything to me and were very kind. I am very grateful for their efforts
They listen and help to understand what happens to you
Dr. Guerra is wonderful. Everyone at this location are very professional and kind.
Wait time was minimal & staff was helpful regarding my results. PA Raygoza is considerate of my needs as a patient. The staff overall, is very helpful.
I am always very happy with them.
All the stuff are very courteous and professional. They are always very helpful and kind.
All the stuff are very courteous and professional. They are always very helpful and kind.
Dr E Guerra is the most awesome person and Dr. Hes knowledgable and explains in details. Ty Dr Guerra.🙏
DATE: 17 APRIL 2025 . THURSDAY
DOING A REVIEW FOR MY FAMILY MEMBER. ATTENDING DOCTOR ROBERT NARVAEZ.MD.. I WILL DEFINITELY RECOMMEND HIM BECAUSE OF HIS MEDICAL BACKGROUND AND EXPERIENCE.
ALSO BECAUSE OF HIS CAREFULNESS, CARING AND TAKING CARE OF MY PRECIOUS FAMILY MEMBER. GIVING DR. NARVAEZ, A HUGE TEXAS SIZE SHOT OUT. JOB WELL DONE SIR. ⭐⭐⭐⭐⭐
FRONT DESK ARE WELCOMING LOVE THE MUSIC OVERHEAD.💙💙💙💙
SCREENING ROOM GETTING THE PATIENT READY TO SURGERY NURSE KENNETH, IS VERY NICE A BREATH OF FRESH AIR. ⭐⭐⭐⭐⭐
RECOVERY ROOM NURSE LILLIE, IS VERY KIND, HELPFUL, CARING AND DEFINITELY FOLLOW THE CENTER POLICY. PATIENT SAFETY COMES FIRST. FOR THAT I DEFINITELY RECOMMEND FOR HER TO THE HIGHER LEVEL OF PROMOTION. I'M VERY GREATFUL FOR HER TAKING CARE OF MY PRECIOUS FAMILY MEMBER. ⭐⭐⭐⭐⭐
ROOM IS WELL ORGANIZED AND VERY CLEAN.💙💙💙💙
THANK YOU KINDLY EVERYONE FOR YOUR OUTSTANDING JOB WELL DONE.👍👍👏👏
HAVE A SAFE AND HEALTHY HAPPY EASTER 🐣🐰🐇🐭
DOING A REVIEW FOR MY FAMILY MEMBER. ATTENDING DOCTOR ROBERT NARVAEZ.MD.. I WILL DEFINITELY RECOMMEND HIM BECAUSE OF HIS MEDICAL BACKGROUND AND EXPERIENCE.
ALSO BECAUSE OF HIS CAREFULNESS, CARING AND TAKING CARE OF MY PRECIOUS FAMILY MEMBER. GIVING DR. NARVAEZ, A HUGE TEXAS SIZE SHOT OUT. JOB WELL DONE SIR. ⭐⭐⭐⭐⭐
FRONT DESK ARE WELCOMING LOVE THE MUSIC OVERHEAD.💙💙💙💙
SCREENING ROOM GETTING THE PATIENT READY TO SURGERY NURSE KENNETH, IS VERY NICE A BREATH OF FRESH AIR. ⭐⭐⭐⭐⭐
RECOVERY ROOM NURSE LILLIE, IS VERY KIND, HELPFUL, CARING AND DEFINITELY FOLLOW THE CENTER POLICY. PATIENT SAFETY COMES FIRST. FOR THAT I DEFINITELY RECOMMEND FOR HER TO THE HIGHER LEVEL OF PROMOTION. I'M VERY GREATFUL FOR HER TAKING CARE OF MY PRECIOUS FAMILY MEMBER. ⭐⭐⭐⭐⭐
ROOM IS WELL ORGANIZED AND VERY CLEAN.💙💙💙💙
THANK YOU KINDLY EVERYONE FOR YOUR OUTSTANDING JOB WELL DONE.👍👍👏👏
HAVE A SAFE AND HEALTHY HAPPY EASTER 🐣🐰🐇🐭
I've been a patient if Dr Alvarez about over 5yrs. He is very knowledgeable, has an excellent bedside manor and explains everything thoroughly. He is an excellent Dr. I never have a long wait at my appts. I'm seen on time and visit is not rushed.
They are in Medical Plaza 2!!
Info texted with address for appointment was wrong. Appt was on time and I did not have to wait long.
Info texted with address for appointment was wrong. Appt was on time and I did not have to wait long.
It’s been over ten years that I have not been able to swallow. Previous doctor diagnosed me for hiatal hernia. I had three consecutive procedures with this same doctor dilating my oesophagus over the years but I was frustrated with not being able to swallow and sometimes with deadly choking episodes. My current primary care physician recommended Dr Otero to me.
Dr. Otero assured me that I should be able to swallow normally again after my procedure. He was so kind and I quite appreciate his encouraging words. I am swallowing again!.
Thanks to Dr. Otero. I will recommend him to the world.
Dr. Otero assured me that I should be able to swallow normally again after my procedure. He was so kind and I quite appreciate his encouraging words. I am swallowing again!.
Thanks to Dr. Otero. I will recommend him to the world.
I was quite pleased with the attention and service provided and the follow-up towards my medical issue. Excellent.