Patient Reviews

We understand that finding a provider that will truly listen to your concerns isn’t always easy. At Adult Gastroenterology Associates, our patients are our top priority. We strive to create a thoughtful and compassionate environment where you can trust that your care is customized to your needs. Take some time to browse through our reviews below, so you can read first-hand about the dedication and care that our specialists provide patients in the Tulsa, OK community.

4.0 Review from H.G. Source: Google Feb 25 2023

"Very direct to the point! No hassle, just true honest opinion. Well trained staff. Like them alot."

5.0 Review from J.H. Source: Google Jan 25 2023

"Dr Nightengale is a great doctor and truly cares about you."

5.0 Review from K.B. Source: Google Dec 25 2022

"Very professional doctor and staff is excellent. Would definitely refer Dr. Markham Nightengale and will continue to use his services."

5.0 Review from L.D. Source: Google Dec 25 2022

"Dr. Nightingale is friendly and thorough. His staff are friendly, kind and very efficient. Couldn't ask for a better gastro facility."

5.0 Review from J.C. Source: Google Nov 25 2022

"Dr. Nightengale has been my gastroenterologist for over 20 years. In my opinion he is as knowledgeable in his field as any person could be. He is very efficient in his consultations with you. No questions left unanswered. I have had multiple EGD’s as well as colonoscopies and his review of the results is always very thorough. I highly recommend Dr. Nightengale."

5.0 Review from B.W. Source: Google Oct 25 2022

"Pleasent demeanor and professionalism, with a sense of humor to boot. His staff were super helpful with making sure I had all my questions answered."

5.0 Review from K.F. Source: Google Aug 25 2022

"Excellent care, staff, location, and procedures. Thank you"

5.0 Review from C.D. Source: Google Aug 25 2022

"He’s Been my doctor for over 20 years. He’s great!"

5.0 Review from P.U. Source: Google Aug 25 2022

"I was pleased with the services that I received from Dr. Nightengale and staff for my colonoscopy/endoscopy procedure."

5.0 Review from G.P. Source: Google Aug 25 2022

"Doctor talked with me before and after the procedure. Seemed to really care about me being relaxed and ok. Would highly recommend Dr. Nightingale."

5.0 Review from J.W. Source: Google Jul 25 2022

"Dr. Nightengale and his staff are wonderful! They truly care about their patients. I was impressed how Dr. Nightengale knew my background before I met him. That really meant so much because that told me he is thorough. I won't go to any other doctor."

5.0 Review from J.M. Source: Google May 25 2022

"Staff was so kind and compassionate! It had been 4 years since my last procedure and Dr. Nightingale remembered me."

5.0 Review from L.E. Source: Google May 25 2022

"I have seen Dr. Markham Nightengale 2 other times and have an up coming appt. He is very professional and kind. He gives lots of information about what he is going to do and what he has found. I am so glad a friend recommended him. I would recommend Dr. Nightengale to anyone."

5.0 Review from C.J. Source: Google May 25 2022

"If you have to have a colonoscopy this is the place to go, they are so nice. They make everything as comfortable as possible. They stay on schedule . Dr. Nightingale has a good bedside manner"

5.0 Review from D.D. Source: Google May 25 2022

"Dr. Nightingale was great. He didn't have all my test results and advised we would reschedule appointment as soon as he did and reviewed them. Surgery not necessary at this time other test to run before that discussion is to be had. I really appreciate his straight forward answers."

5.0 Review from B.D. Source: Google May 25 2022

"Just completed 3rd colonoscopy procedure done by Dr. Nightengale. He spoke with me prior to the procedure in his usual pleasant manner. A detailed report including photos was provided afterwards. Checking in at the lobby was efficient. Initial prep by nurse and anesthesiologist went smoothly. Checkout also. All staff from checkin to checkout were pleasant."

5.0 Review from S.C. Source: Google May 25 2022

"Very thorough by listening and asking questions to get the best diagnosis and care. He is friendly and personable. I was at ease when I left the office knowing the best way to take care of my problem is to have a colonoscopy/endoscopy to get a thorough diagnosis. I asked questions that he took the time to answer and explain his answers. I highly recommend Dr. Nightengale. He is an excellent gastroenterologist!"

5.0 Review from S.H. Source: Google May 25 2022

"Dr.. Nightingale has been.my GI doctor doe years. He has always been knowledgeable and professional. I highly recommend him!"

5.0 Review from S.R. Source: Google May 25 2022

"Dr. Nightingale is an excellent physician. He is very caring and does not rush through an appointment. He listens and is compassionate."

5.0 Review from E.F. Source: Google May 25 2022

"Dr. Nightengale has performed at least six procedures on me over a number of years. Each and every time his work has been very professional, he has always been on time and provided me with the results very quickly. He always makes me feel very comfortable before and after every procedure and I have never had the slightest amount of pain or discomfort. Besides being a wonderful doctor, he is a very kind and caring person. I also cannot say enough good things about his staff. They have things organized to go like clock work. I know I will need another procedure within the next two years and I have absolutley no fear or anxiety about having it done."

5.0 Review from G.E. Source: Google May 25 2022

"I’ve been going to Dr. Nightengale since 2014. I find him to be very knowledgeable and companionate. As it I have an appointment with him in the near future for an evaluation. He’s the best in his field."

5.0 Review from D.G. Source: Google May 25 2021

"Dr. Nightengale was my Mothers Dr., and is now mine. He is very knowledgeable, pleasant, professional, and caring. I have recommended him to others and will continue to do so."