Patient Reviews

GI Alliance physicians are among the most reputable and distinguished gastroenterologists across the nation. Focused on clinical excellence and patient-centered care, our specialists seek to be the partner you need in your quest for better health. We value patient feedback and appreciate every review we receive from those we are privileged to treat. For your convenience, we have gathered a collection of reviews, stories, and testimonials provided by patients who have visited our practices. We welcome you to explore the feedback below to learn more about what it means to be a patient of GI Alliance.

5.0 Review from S.A. Source: Google Nov 16 2022

"I have known Dr Mark Nightengale for years, have trusted his colonoscopy experience and will continue to reschedule whenever he recommends. A great friend as well."

5.0 Review from K.R. Source: Google Nov 11 2022

"Dr. Nightengale always gives me as much time as I need when it comes to Questions and answer to all my questions. I ask for a better doctor and I would highly recommend him to anyone."

5.0 Review from B.S. Source: Google Nov 11 2022

"I've been seeing Dr. Nightengale for years and he is wonderful! He makes me feel comfortable with every procedure and is patient with all of my questions. He doesn't try to rush out of the room, which is nice. I've never seen him without a smile on his face."

5.0 Review from J.C. Source: Google Nov 02 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 M.A. Source: Google Oct 25 2022

"He was confident in his approach which was encouraging."

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

"Dr. Nightingdale's staff is Tulsa's best in colonoscopy's in my opinion. His staff has preformed my last 4 colonoscopys. Each time his staff was always very professional and courteous. I was in and out in under 1 hour. I will go back to him for my next one as well! I can't say enough Great surgeon Great Staff!!!"

5.0 Review from B.W. Source: Google Oct 10 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."

4.0 Review from M.D. Source: Google Sep 12 2022

"Dr. takes the time to talk with you and explain your condition. He put me at ease which allowed me to ask questions concerning treatment of my disease. The staff seem a little less patient."

5.0 Review from K.F. Source: Google Jul 26 2022

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

5.0 Review from C.D. Source: Google Jul 26 2022

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

5.0 Review from K.A. Source: Google Jul 20 2022

"Dr Nightengake provided excellent service. He and his nurse were thorough in explaining my procedure, doing my procedure was with ease and my wait time was less than 5 minutes in the lobby! One and done!"

5.0 Review from S.W. Source: Google Jul 18 2022

"Dr nightgale is a awesome doctor he makes u feel comfortable and safe with him! He ginuine and cares about his patients"

5.0 Review from J.W. Source: Google Jun 28 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 N.K. Source: Google Jun 28 2022

"The facility and all staff are attentive, thorough, caring and cordial. They make you feel comfortable in a speedy, quick process from start to finish."

5.0 Review from M.J. Source: Google Jun 28 2022

"Awesome Job. I've completed my frequency card. I get the 5th one free... .Yahoooo"

5.0 Review from P.H. Source: Google Jun 21 2022

"I have been a patient of Doctor Nightingale’s for about 5 years now. I always feel safe & heard by him. He has done both my upper GI & my colonoscopy. I get an upper GI yearly because of stomach cancer running in my family (my choice) so I’ve experienced his team many times. I most certainly would & will recommend Dr Nightengale as the best Gastroenterologist in Tulsa! Thank you Dr Nightengale for your care!"

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

"He listens, does his best to help with your care."

5.0 Review from A.R. Source: Google May 21 2022

"Dr. Nightingale is the best for problems with your colon."

5.0 Review from L.B. Source: Google May 11 2022

"Very nice staff and Dr. Markham Nightengale M. D. Is very good and explainable on his findings and great with his patients"

5.0 Review from D.W. Source: Google Feb 03 2022

"He is very sincere and totally focused on your care and what is best for you. I would recommend him everyday all day!"

5.0 Review from M.L. Source: Google Feb 02 2022

"Been going to Dr. Nightingale since I had my first colonoscopy 30 years ago. He is very friendly, direct, professional, concerned about you when speaking with you. He’s a great person. His staff is very helpful and professional. The center where the procedures take place is clean and comfortable. Both the Dr.’s office and the center are taking Covid precautions."

5.0 Review from S.C. Source: Google Dec 16 2021

"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 K.K. Source: Google Dec 05 2021

"Best liver doctor ever. Explains everything so I could understand it. Always polite and never made me feel I was taking to much of his time. Talked me thru procedures that was hard to get thru. I'm very grateful for Dr. Nightengale."

5.0 Review from G.E. Source: Google Dec 05 2021

"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 T.C. Source: Google Nov 13 2021

"Everyone in the office was so super nice from the front desk all the way to the recovering nurse. It's just a very great experience nothing to fear just really wonderful place wonderful doctor and wonderful nurses. I've gone to. Dr. Nightingale for two colonoscopies now, he has taken wonderful care of me. I totally put my trust in him. I would recommend him to anyone and everyone."

5.0 Review from M.B. Source: Google Oct 27 2021

"I highly recommend Dr Nightengale. He is great at what he does and has an excellent bedside manner."

5.0 Review from S.R. Source: Google Oct 12 2021

"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 S.H. Source: Google Oct 03 2021

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

5.0 Review from C.W. Source: Google Sep 17 2021

"I visited Dr. Nightengale for the first time in September. He was extremely nice and made you feel comfortable. His nurse was wonderful as well. We’ve got tests scheduled and I feel confident that he’s going to get me lined out."

5.0 Review from L.E. Source: Google Aug 29 2021

"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 I.N. Source: Google Aug 28 2021

"Dr. Nightingale he is a really good doctor he's sweet he's kind of funny and they treat you like family there I would recommend dr. Nightingale to anybody he is awesome and he knows what he's doing and he explains everything very well that's my family I love them I'm telling you you need to go to him now he's really good"

5.0 Review from C.J. Source: Google Aug 27 2021

"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 G.P. Source: Google Aug 12 2021

"Dr Nightengale has been taking care of me for around 15 years. Every interaction is completely reassuring, and every procedure very comfortable. For me, it couldn't be better."

5.0 Review from G.N. Source: Google Aug 10 2021

"This was as good as it gets for a colonoscopy. Everyone was very cordial and professional. Had absolutely no complications from procedure. See you in five years!"

5.0 Review from D.D. Source: Google Jul 22 2021

"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 A.T. Source: Google Jul 20 2021

"I recently had a colonoscopy and an upper GI which Dr Markham Nightengale performed. I was totally happy with his services and my care from his staff. I was complete informed on how to take my prep and how it would work. I arrived on time the next morning and filled out my papers I was taken back to get prepared and his staff was so nice and told me exactly what they were going and how it would go. When it was my turn and by the way it was on time I was taken back and they did the procedures and then off I went to recover. Everyone that I came in contact with was so nice and pleasant. For a procedure no one looks forward to it was no problem and Dr Nightengale came in before I left to let me know what he had done and that he had told my husband already. I was completely satisfied with my experience with him. Thank you Dr Nightengale"

5.0 Review from K.C. Source: Google Jul 20 2021

"Very pleasant , i was surprised to meet a doctor that seems like he really cared . i am kind of spooked with my condition but Dr Nightengale assured me that everything would be okay , those were the words i wanted too hear . Thank you Dt . Nightengale and see you soon"

5.0 Review from B.D. Source: Google Jul 16 2021

"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 J.F. Source: Google Jun 02 2021

"I have been a patient of Dr. Nightengale for over 10 years. He is so kind, thorough, and has the best bed side manner. He has treated my c.diff problems, post gallbladder issues, and reflux. Whatever your GI symptoms are, I highly recommend him!!!"

5.0 Review from E.F. Source: Google May 31 2021

"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 J.B. Source: Google May 30 2021

"I first want to say the Dr Mark Nightingale he did what 80% doctors don't do he listened to the patient he said there on the bed next to me he'd listen to every word I said as long as I didn't take too long like saying the same thing over and over and then he examined me and if he was not touching the spots that did not pertain to what I was saying he allowed me to show him and I walked out of there with a completely different feeling I have been suffering for 6 years losing weight from 240 to 167 standing six six so skinny I'm about to blow away dying the first visit he said my life I appreciate him so much to the point if I saw him I would break down in front of him and shine his shoes he probably wouldn't let me lol but from what he did to me I know I will have 100% recovery after 6 years of brutal pain thank you Mr Nightingale can't wait till my next visit thank you very much Vincent l Jones"

5.0 Review from J.M. Source: Google May 28 2021

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

5.0 Review from T.S. Source: Google May 23 2021

"He is a very positive and uplifting dr. The first appointment that I had with him. He gave me a lot of Hope and gave me a lot of confidence and knowing that he would be a good doctor and would do everything for me that he could that could possibly be done anyway about my situation. I left the office with the with the confidence and feeling that I had a chance to beat this ugly disease I have and great news it happened exactly that way. He definitely seems like the doctor that would go that extra mile for you or any patient, and I feel very fortunate that I have lucked onto him as the first liver doctor, that that I searched for in a very careful way."

5.0 Review from D.N. Source: Google May 22 2021

"He is always friendly and listens well. He is board certified and did his residency at Mayo Clinic. I highly recommend him."

5.0 Review from D.G. Source: Google May 01 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."