He gives great care and is very thoughtful and caring. The office wasn't so great when I first started going there, but they have definitely improved. read more

As a physician referral source with over 45 years in healthcare, and also a dedicated patient advocate, I rarely post negative reviews. However, after being sent to Dr. Gilbert Simoni's office for a FibroScan due to elevated liver enzymes and fatty liver, I encountered a grossly negligent error. The office told me the machine had been calibrated in November 2025, but the results I received indicated a P3 level, dangerously close to cirrhosis. Despite my request, I advocated for additional blood work, which contradicted the scan. I then went further, paying $4,800 for another FibroScan and an MRE, both confirming no fibrosis. I offered to help train the technician and verify the machine's quality, given the recent calibration, yet the office refused. They still demanded a $170 payment at the end. I am sharing this publicly so both patients and physicians are aware: a mistake of this magnitude, despite read more

Do not get the transoral incisionless fundoplication surgery with Dr. Simoni. My husband got this surgery about 2 years ago with Dr. Simoni at a hospital in Riverside. After the surgery, my husband wasn't able to have any follow-up appointments with Dr. Simoni because he left the hospital. My husband has had horrible complications since the surgery...shoulder pain, nausea, and pain when swallowing. Every single emergency room/doctor he's gone to has told him they don't see a problem, but also that they're not well informed on the surgery so that thier may be an underlying problem. Mind you, he's gotten this response on 5 separate occasions. Finally, he was able to track down Dr. Simoni and get a referral from Loma Linda to his practice. The clinic was informed that this is an emergency situation and that my husband is basically on a liquid diet 2 years after his surgery right now. even then they still refused to schedule an appointment for him. Dr. Simoni said they needed a referral from the clinic/hospital where the procedure was performed. Why this is necessary when he already has a referral, and he was the doctor that performed the surgery, is beyond my comprehension. It's extremely unprofessional and says a lot about a doctor when he's making it nearly impossible to schedule an appointment with on of this patients in an emergency situation. My advice: go to a doctor who actually cares, because when complications happen, you don't want to live through the nightmare we're going through and it be handled with such indifferance/carelessness. read more

I am really happy to be seeing Dr Simoni. His office has been so amazing and kind. I will be seeing him for a procedure soon and I feel confidant that everything will be fine. The reason I think this is because about 5 years ago he found that my husband had liver cancer. No one else discovered it. He has since had a liver transplant and is doing very well. We both credit Dr Simoni with saving his life. read more

I liked him very much. He gave me some lifestyle/nutrition advice which definitely helped. The problem? His front office is extremely rude. I ran into a friend very recently who told me they quit him for the very same reason. I canceled a colonoscopy 72 hours prior & rec'd a letter from his office shortly thereafter that stated they would no longer treat me. I've never been "fired/canceled" from a medical practice. read more

Bait-and-switch! I jumped through all the hoops-- uploading my previous records and filling out the forms before they would even schedule an appointment. Then I drove past dozens of gastroenterologists between Santa Maria and Thousand Oaks to see Dr. Simoni. If I had read his Yelp reviews prior to making the appointment, I probably would have gone elsewhere. I went to all that trouble for one reason: His website prominently features Trans Nasal Endoscopy and Wireless Capsule Endoscopy. I have struggled with recurring bouts of anemia, and I wanted to rule out gastrointestinal bleeding, but I didn't want to have another upper endoscopy, and I can't have a colonoscopy due to an anatomic anomaly that prohibits passing a scope through my intestines. I brought a bullet point summary of my history and my reason for being there, which I wanted to go over with the doctor. When I mentioned it to his medical assistant, she offered to scan it into my record. I agreed, but I asked her to bring it back, so I could go over it with the doctor. Instead, she gave it to Dr. Simoni's PA and she and Dr. Simoni apparently read and discussed it before he came into the exam room. That IS NOT what I asked her to do! When Dr. Simoni came in, he quickly shot down both Trans Nasal Endoscopy and Wireless Capsule Endoscopy (which is lauded on his website for the ability to detect bleeding in the small intestine). Instead, he insisted that I needed another upper endoscopy and a colonoscopy. I explained why I didn't want to have an endoscopy and why I couldn't have a colonoscopy, and he basically said that my other gastroenterologists were incompetent and he could do it. Navigating a tortuous colon is very difficult and carries a higher risk of perforation, which is why most gastroenterologists won't attempt it. Note that under the best of conditions, the perforation rate of upper endoscopies and colonoscopies is 1 in 100, and of those, 25% are fatal! That means your risk of dying from one of those procedures is 1 in 400 (and a friend of mine nearly did)! I'm guessing the odds are even worse with an arrogant, overconfident doctor. At one point, he asked me if I ever had canker sores. I replied, "Once in a while." He said, "You have Crohn's disease." I DO NOT have Crohn's disease! (I have NO Crohn's symptoms.) My canker sores are caused by a dormant virus that surfaces if I eat too many nuts, thanks to an arginine/lysine imbalance. Malabsorption CAN cause a B12 deficiency and result in canker sores, but my B12 level is fine. He never asked. I feel like I was duped by a bait-and-switch tactic! The promise of those alternative procedures lured me in, and then he attempted to "upsell" me by insisting on a much more costly and risky plan. As other reviewers have mentioned, Dr. Simoni seems to be all about the money. He won't accept you as a patient until he sees your records. I'm guessing he saw mine and thought I was not only good for an endoscopy and a colonoscopy, but possibly a TIF procedure for my hiatal hernia and a cholecystectomy (gall bladder removal) referral, as well. He also accused me of spending too much time with "Dr. Google." Yes, I absolutely do research my conditions and learn about them online! I wonder why Dr. Simoni has a problem with well-informed patients? My advice would be to avoid this practice. read more

Dr. Simoni & his staff took excellent care of me throughout my colonoscopy. I was weirdly looking forward to experiencing my first colonoscopy. The entire process from start to finish went smoothly. Thank you Dr. Simoni. read more

Dr Gilbert Simoni your responses to all of your negative reviews are appalling!! You have such sarcasm, to all of these patients who needed you to help them out of pain!! You abandoned all of them and then have the gaul to accuse your patients of Abuse and Rudeness!! Your accusations are DANGEROUS and are disgusting you put many patients in danger with their health!! You referred me to other specialties of doctors, and they all have the same horrible reviews!! And now those doctors are getting negative reviews with your negative reviews! Dr AZITA SIMONI you referred me to for dermatology in Newbury Park the staff and so called Dr AZITA SIMONI are a complete joke!! Rude, keep you waiting. Doctor seems confused as well!! DO NOT GO TO THIS dermatology practice they are extremely rude on the phone!! read more

Awesome GNT Gastroenterologist! Fantastic caring 'bedside' manner. Dr. Simoni's suggestions of additional or multiple tests are demonstrations of his caring curiosity. Explains in down to earth yet technically clinical terms, which provides clarity and confidence. The office staff is attentive and caring as well. The office continues to modernize, with online patient check-ins and records and a patient web portal. read more

Saw this doctor a long time ago when I was very sick with Crohn's disease and severe gallbladder problems. I had lost a lot of weight and that was the only symptom he cared to address. He told me to drink several cans of ensure every day and come to his office every day to get weighed on his scale. Not really convenient and did nothing to address the underlying cause of the weight loss and severe pain I was in. I beat it out of there fast and didn't look back. Terrible experience. Very humiliating. 8/2/2021 I am responding to your reply to me below. It is my maiden name. I am now married. That, and the fact that it was 15-20 years ago is why you have no record of me as a patient. I am neither mistaken, nor do I have an incentive to write negative reviews of healthcare providers, as easily evidenced by my numerous positive ones which you conveniently ignored. I have also left glowing reviews for several vets aside from VSEC. I do not appreciate you wishing me "a better life" as I have a wonderful life and currently have a great team of health care providers. Your blatant sarcasm makes it obvious why you are not one of them. read more

Visited this Doctor for a consultation and procedure. Had my procedure done at RMC surgery center on 3-14-2023.Dr.Simoni has excellent bed side manner, and treat his patients wonderful. His staff is amazing,and caring. I am happy that RMC has caring physicians and staff. During consultation, he also had me checked out for another concern he had. Excellent doctor. Thank you Dr.Simoni!!!! read more

Probably the worst practice I've ever been to, front to back. Unfortunately Dr Simoni is equipped with about one solution (which you will see the marketing material of plastered through the entire practice). We may not always realize it, but medicine is a money making business and that was made very clear to me here. If you're looking for a practice to genuinely care for you and your best interest, keep looking. read more

Fantastic GI doc. Caring, thorough and attentive to your medical care. Extremely knowledgeable in his field and on the cutting edge of both medical and office technology. Staff is extremely professional. If you need a GI Doctor, this is the man to see. read more

I am pleased with Dr Gilbert Simoni and the staff at Advanced Gastroenterology. Dr Simoni is kind, calm and knowledgeable. He takes the time to answer my questions and explains his comments fully. I highly recommend Dr. Simoni read more

Dr. Simoni, while a decent practitioner and surgeon, unfortunately has some of the absolute rudest women working in his office, ever. Good luck having a civil, even remotely polite conversation with the office staff. When we decided to switch to another provider and informed the manager of the reason for switching, no response or apology whatsoever. Avoid this practitioner and his horrid office staff at all costs. There's plenty of wonderful, pleasant, and polite gastroenterologist in the area. Quite bluntly, his office staff sucks, and they all need a lesson in professionalism and customer service. read more

This doctor is not bad, he has a gentle demeanor and would be great with kids. He rightly recognized that I needed to get my gallbladder out but after that he isn't as caught up on literature/science as I would like. He subscribes to the theory of the low-fiber gastroparesis diet, which my GP also thinks is junk. I don't recommend if you have something out of the ordinary necessarily, but he is a fine doctor otherwise. He did refer me to a surgeon who was a complete pompous jerk, but I ended up going with David Chi who is very good. read more

Dr. Simoni is an exceptional physician, compassionate, caring and wise beyond his years. His manner is positive, relaxed and respectful. The TIF procedure he performed is relatively new and I feel he went above and beyond to ensure my concerns were addressed. The procedure can be life changing and his knowledge and expertise certainly make him one of the most qualified physicians to perform the procedure His office is beautiful and clean and the staff always friendly, courteous and responsive. I am fortunate he was recommended to me and I pass that recommendation to anyone in need of a G.I. specialist. He is the best. V.J. Fuller, Los Angeles, CA read more

My GI problems: GERD, hiatal hernia, Chron's disease. Dr. Simoni has made a big difference in improving my quality of life. I went to him seeking the transoral incisionless fundoplication (TIF) which restores a working esophogeal sphincter to treat GERD. I am 7 months post-op now with total resolution of my GERD symptoms and no complications. Every patient is different and there are risks to all medications and surgical interventions. Dr Simoni is great at walking me through the process with rationales for each step. I like to hear the stats and research which he is quite good at citing off the top of his head. He discussed the risks and benefits with me for each decision we made. I made another appointment through the office staff whenever I completed a test or had a concern I wanted to address. I really appreciate his asking if there is anything else he can do for me at the end of each visit and he keeps asking until I say no thank you. I had two gastroenterologists previously. I had an endoscopy and colonoscopy being told to follow up in 10 years, nevermind all the symptoms, before I went to see Dr Simoni. We started looking for the sources of my problems. There were several studies that I did. Many things were ruled out. Finally one caught the problem. Dr Simoni offers the PillCam endoscopy which images your whole GI tract with thousands of pictures just by swallowing a little capsule and took 8 hrs for me while I went about my day. He was able to see the ulcers and edema of Chron's disease that the endoscopy and colonoscopy did not. We treated the Chron's then moved on to assessing whether I was a candidate for the TIF procedure. I was also born with a nerve disease that can reduce the esophogeal motolity strength needed to get food past a new competent sphincter valve. Dr Simioni was able to show that I had the needed strength to swallow. All together there were approximately 6 studies I had done but my case is more complicated than GERD alone. The TIF was done working together with a general surgeon, the awesome Dr. Chi, because I needed a hiatal hernia repair at the same time. I have not had GERD since they day of surgery. I stopped taking protonix when Dr Simioni said to and after a week or so of a vague stomach irritation which resolved I don't need PPI's at all anymore. My life is much improved and I can focus on other things now thanks to Dr. Simoni and his staff working with me. I also have two friends who had the TIF and they had good things to say too which is why I went to Dr Simoni. A note about health insurance companies. Insurance companies have spent billions of dollars buying back their own stock and recording record profits while blaming the ACA for their over charging and despicable differences between revenue and dollars spent on paying for healthcare. The use of high deductibles prevents people from using their coverage and this is used as a tool to keep profits high. Make sure that you have the best coverage you can access and after that don't let up if your insurer says no the first time to a step in the process. I had to fight hard with my insurer but after a year delay, I was able to get my insurance company to pay for an essential test. Keep appealing and using all the leverage you can. I had GERD for 25 years. Suffered pain, aspiration, coughing and lost sleep, lost relationships, money on medications, emphysema diagnosis on xrays after aspiration, pneumonia, risk of cancer, decreased nutrient absorption. It was worth the time for the next 25 years to be different. Don't miss the opportunity to get treated while pre-existing conditions are not excluded. I don't mind discussing more about my experience with the TIF procedure if you contact me. Shawn Porter RN, BSN read more

I found that this Dr. has a severe cleansing protocol for a colonoscopy that required a strong laxative two nights before the procedure, then two more strong laxatives the night before, and another the morning of, instead of just the usual laxatives the night before and morning of. This left me feeling like I had a bad case of norovirus. I was concerned with this happening, and when I called the office to question it, had my concerns dismissed by office staff. I would never go to this Dr again due to his draconian clean out called PrePoPik, that used Magnesium citrate and Ducolax, in addition to Prepopik powder. read more

I would give no stars if I could. Dr is ok but the office and billing practice is atrocious. When I went for a procedure, I was not told that they were not contracted with any insurance company. So I paid what conveniently was my 10% had they been contracted. 6 months later, I receive a bill for $798. I called and was told that they are not contracted and this is my balance. The gal said they tell everyone that they are not contracted with so it is in me. If I was told that, then I would have questioned and went to the hospital where it was 100% covered. Or, I would have paid in full as I did with the amount that they told me. I think this is bad billing practice and they are trying to get all the money they can. read more

Office staff is super friendly , prompt , and organized. Dr Simoni listens, and takes the time needed to address your issues...very professional and personable. read more

I had seen Dr. Simoni several years ago, and he treated me for chronic pancreatitis. I thought we had a good doctor-patient relationship. So when my endocrinologist informed me that recent test results indicated I may have a problem in my liver or pancreas, I went to see Dr. Simoni to try to get his help in investigating this problem. Dr. Simoni ordered an abdominal MRI and a series of specialized tests (done at Quest Diagnostics). However, when I went back to see Dr. Simoni to find out the test results, he would not see me. His staff informed me that Dr. Simoni had decided I should see a different gastroenterologist, and that I had been "discharged from his practice." He would not go over my test results with me, and so far neither Dr. Simoni nor his staff has made my test results and other records available to the follow-on doctors I am seeing now. The information he could provide would be very helpful, but the doctors I am seeing have stated that Dr. Simoni's staff is KNOWN FOR BEING UNCOOPERATIVE and for refusing to work with other physicians in the area, and they do not expect any help from him. It turns out that I have a life-threatening tumor on my pancreas, and Dr. Simoni's failure to help or at least be cooperative has delayed my treatment. In summary, I believe I have been treated despicably by Dr. Simoni and his staff, and that they have acted in an unethical and unprofessional manner. I certainly CANNOT recommend Dr. Simoni to anyone needing gastroenterology help. read more

Dr. Simoni and his staff are top notch professionals. If you find yourself needing anything gastro related he is the expert to go to. He has helped me with routine preventative issues as well as performing a TIF procedure to alleviate acid reflux. Highly recommended him and his staff. read more

Dr. Simoni is by far the best Gastroenterologist I have ever gone to. I have a chronic condition that all other doctors in the area could not take care of. He changed my life after just one visit, and that was 5 years ago. Amazing... I see him every 6 months and cannot say enough wonderful things about him. read more