Excellent service and excellent care. Katie did an outstanding job. She explained everything carefully and answered all of my questions. The front office was very accommodating with respect to my appointment needs. read more

My experience with Dr. Yi Zheng was very disappointing. Appointments were always late and often felt rushed. Every appointment was late, including my first visit. (more than 30 minutes late with no apology) Follow-up care was also lacking. My ultrasound results (which included medical terms I did not fully understand) were posted on the patient portal by the ultrasound provider, but Dr. Yi Zheng did not add any explanation, comments, or follow-up to help interpret the results. My endoscopy appointment was also delayed, and afterward I was not given an explanation of what was done or any immediate post-procedure discussion. Another phone appointment was automatically scheduled without discussing it with me first, and again the doctor joined the call more than 30 minutes late. The conversation lasted only a few minutes and felt rushed. In contrast, my previous gastroenterologist would speak with me before and after procedures and provide results directly through the patient portal, without needing additional billing phone visits for basic follow-up. Communication through the Tebra patient portal was also an issue, as I did not receive a response when I requested assistance and asked about changing a provider for a gastric emptying study. When I contacted the office, staff were unable to confirm whether messages are regularly reviewed by the doctor. Overall, this was one of the most unsatisfactory experiences I have had with a medical provider in terms of communication, follow-through, and coordination of care. I would not recommend this provider. read more

Dr Zheng was very professional, explained everything well. Highly recommend. Made me relax and gave me the time I needed.

Excellent communication with entire office team. Procedure went smoothly and without incident. Always willing to speak or text as needed. Highly recommend Dr. Zheng and her team. read more

Excellent communication & updates. Solid approach with frequent and professional customer service.

I recently had a colonoscopy done by Dr. Yi Zheng, and I had a great experience. She's very knowledgeable and took the time to explain everything clearly, which really helped me feel at ease. She answered all my questions and made sure I understood what to expect before and after the procedure. Dr. Zheng is professional, kind, and easy to talk to. I feel confident having her as my GI doctor and would definitely recommend her to others. read more

I had a very disappointing experience with Dr. Zheng after my Colonoscopy and EGD in September. Before the procedure, I called the office to confirm that there would be no extra charges, and her assistant assured me they found none. However, after the exam, I started receiving emails demanding a payment of about $600, without any invoices or billing details. The payment link led to a suspicious-looking page that felt like a financial scam. When I called the office, they transferred me to their "financial team." After a long hold, someone finally answered and said they would speak with Dr. Zheng and call me back, but I never heard from them again. Instead, I continued receiving payment notices, and the amount even increased by $35 in November. The whole situation feels unprofessional and confusing. I plan to contact my insurance company and the medical board about this matter. read more

Yi Zheng - Payment portal from the link in Dr. Zheng's email. - Gastroenterologist Near Me - Walnut Creek, California

I had a colonoscopy at Premiere Surgical Center. The staff were professional, efficient & attentive. Dr Yi Zheng performed the colonoscopy. No issues post procedure & she gave me the results before leaving. read more

Dr. Zheng is amazing! She is very knowledgeable and friendly. I highly recommend Dr. Zheng. read more

I can't say whether this doctor is competent, although there were no physical problems after a regular colonoscopy. My wife, who is Chinese, had this done, and it was purely preventative, and supposedly no cost outside of insurance. But she had one done long ago at this office before Dr Kung retired, and there was an initial billing problem which got straightened out. So, this time, we went to a lot of trouble to make sure it was billed correctly. Insurance said it was fully covered, and we communicated with Dr Zheng beforehand to let her know there were no issues, just a screening. Well, after the procedure, we started getting bills, for over $1000 from her, from the anesthesiologist, and from some other doctor. I contacted the billing dept, who said they don't know anything other than what the practice tells them. So I called the practice, and they said they don't know anything about the billing. Nobody would take responsibility or offer to help straighten it out. My wife had a messaging address for the doctor, and we messaged her. She got upset, said it was billed correctly, and then blocked us. We got the same runaround from the anesthesiologist. So we began the long process of dealing with the insurance company, who promised to contact them and get back to us. Guess they had as much luck as I did, and I never heard back, so had to contact another insurance agent, who sent it out for review. After about 6 months, we are only getting bills from Dr Zheng's office, for about $300, and I finally paid it after giving up. She wants $185 for the preliminary office visit, which is required, where she does nothing that can't be done via mail - just the instructions for the procedure. Insurance said that was billed as diagnostic, so not covered. There was also an unwanted addition for an endoscopy that we said we did not want, but I paid it to be rid of this group of sleazeballs. Definitely avoid them if you have a high deductible insurance plan, unless you have lots of medical issues and meet your deductible for the year. Otherwise, you will be paying out-of-pocket for a hefty fee. read more

Yi Zheng is a doctor of Gastroenterology & Hepatology. She is attentive and communicates well. She is one of the few doctors, in the Bay Area, to have Hepatology equipment in her office. I highly recommend her for treatment of the liver. Gail Roman read more

Dr. Zheng was concerned, thoughtful in her questions and answers and helpful with her recommendations.

I'm disappointed that I can't give her a negative rating. I had the same experience as BDK. She is by far the worst experience I have ever had. She is part of John Muir, yet she has never to this date put any records in that crappy John Muir MyChart software that they force on their patients, although she has had 3 months to do that, she overbilled for a failed colonoscopy which failed because SHE ordered the wrong prep, wasting 5 hours of my time, because they overbook, and $100 in cab fare only to be told I had to come back which will never happen. On top of that, their surgical facility has a grungy waiting room, with maybe 8 chairs although there were at least 25 people there. She has pulled a number of other stunts that have caused me to file a complaint with the State Medical Board. She has refused to comply with the conditions of my PPO insurance so I reported her to Anthem Blue Cross. I sincerely hope they dump her. Her staff is completely incompetent and disorganized, and whoever answers her phone barely speaks English, and does not understand questions. If you leave a message, 3 people will call you back, none of whom actually do anything you request. An email, and 2 direct conversations notifying her I did not have a ride or a babysitter two days before a scheduled endoscopy resulted in the failure of any of them to take me off the surgical schedule. I returned one of her staff's call, and she just kept repeating "she call you back" without even asking who I was. How is anyone going to call me back if her receptionist is too stupid to ask anyone who calls for their name or information? read more

I was recommended by my physician to schedule a fibroscan with Dr. Zheng. It took 4 calls and 3 weeks to schedule a pre scan call with Dr. Zheng. Then what was a 2min call and a copay of $150 she scheduled the meeting for the following week. Seemed like I could have scheduled the scan without her call. Then I am sent a Labcorp form for bloodwork 3 days before the scan. If I had know bloodwork was needed I would have scheduled the scan further out giving myself sometime to get blood drawn. Overall bad communication from her office and a lack of professionalism from her assistants returning my initial voicemails and setting appointments. read more

Dr. Yi Zheng is highly recommended, I did few tests over two years, it has been very helpful and professional.

Katie performed the liver scan. She is amazing. Katie was the only person in the office. She did double duty. Her attitude and work ethic is commendable. She was a real trooper. Katie is a good example of an employee filling in when necessary without complaints. I commend her for her spirit and work ethics. Please extend my appreciation and gratitude for a job well done. read more

Very knowledgeable, professional, and caring physician. Staff very friendly and organized with several reminders for my appointment. They have the fiber scan in their office which makes it easier. I am very happy with Dr. Zheng and I highly recommend her. read more

Dr. Zheng seems fine in terms of her medical care. However, her billing system--well it's not a billing system because she doesn't bill me. Her staff requests payment before you even have the appointment. (btw--I have no outstanding medical bills and always have paid her and any other medical provider promptly and fully). This is causing me several problems. Because she does this, I'm now in a position of overpaying my beginning-of-the-year Medicare deductible. I have also already paid her an amount that my Medicare Summary Notice states exceeds the maximum I may be billed for the visit. But like I said--she doesn't bill--she gets her money (wrong amount) up front. This also entails having a different provider have to redo his billing. Very very unhappy with this. read more

My primary care doctor sent referrals to two offices. Yi Z's office texted, called, and emailed me repeatedly, but I didn't respond because I saw some concerning reviews online. A week later, they scheduled an appointment for me on their own--without me requesting it or giving any approval on that specific time slot. I've never experienced anything like this before. It makes me feel like they're desperate for business and ignoring the concerns that other patients have posted online. read more

Dr Zheng is an extremely knowledgeable physician that makes you feel comfortable right away. I have no worries about the upcoming procedures! read more

I appreciated the quick response and information prior to my colonoscopy. Instructions were clear and I knew what to expect. The day of the procedure went smoothly, and the doctor came to check on me and give me a quick review to be finalized a week later. All the staff was responsive and the nurses very kind and professional. read more

If your Primary Care Physician gives you a referral to this doctor, do yourself a favor and request someone else. She is negative, judgmental, has no bedside manner, and greedy. I had to pay a copay on the first visit (as expected), and she spent 20 minutes with me and her back to me the whole time, while she fired off questions and stayed focused on her computer screen, except for when I said "At least I'm not diabetic" (A1C is 5.9) to which she turned around and said "Not yet!" What kind of medical professional says that? Next visit is for a scan, with another copay (as expected), and I didn't even see her (just a tech). Two days later, her staff calls to say she'll have to call me back to give me my results (but not until after I pay another copay). She calls back 45 minutes later, and spends 10 minutes on the phone to explain my test results (because I paid the copay). I have NEVER had to pay a copay to any doctor, just to hear my results over the phone so that she can bill my insurance $500 (or more) as an office visit (not just a phone call). She is clearly greedy, unethical and only in it for the money with no care or regard for her patients. In my opinion, she should have chosen a different career path, perhaps in medical billing, since that seems to be her true specialty. Her office staff is inept too. AVOID this doctor and her office at all costs! read more

I came to Dr. Zheng after having a bd experience with another G.I. She fit me in quickly for a consultation when I was very sick. She is very nice, understanding, kind and listens. She explains things well. She has a very good "bedside manner." Her office staff is friendly and kind. Easy to schedule appointments. read more

I've been a patient of Dr. Zheng since 2020, when she took over the patient records of Dr. Henry Kung, who retired. I had two procedures in 2023, a colonoscopy and an upper endoscopy, and there were no issues with either procedure. Recently, because of some bowel obstruction issues, my surgeon requested that I get a capsule endoscopy of my small intestine. I swallowed the capsule in Dr. Zheng's office on March 6, 2025, and mailed the capsule back to the CapsoCam company on March 8. Dr. Zheng's instructions said that I should receive the results within 2 to 3 weeks. At the end of March, I left for a previously scheduled vacation. I assumed that I would hear something from Dr. Zheng's office while I was away, but I heard nothing. When I returned, I called Dr. Zheng's office to ask about the capsule endoscopy results. I was told that they'd contact the doctor and get back to me by the end of the week. I got no response. The next week I called again, and again they said they'd get back to me by the end of the week. Again, no response. The following week I called again and threatened to file a complaint with the Medical Board if I can't get my endoscopy results. This time they called back and scheduled a telephone call with Dr. Zheng, for May 12. On May 12, more than 2 months after the procedure, Dr. Zheng called to give me the results. She said the capsule showed nothing to report! I asked several questions trying to get any kind of data from the procedure, but she couldn't tell me anything. I asked her to send whatever she had to my surgeon. She said that she'd already sent him the report, but she would send it again. The following week I met with my surgeon to see if he had received the report. He said he hadn't received anything from Dr. Zheng. I've seen a lot of doctors in my time, but I've never been treated like this. read more

Outstanding care. Great communication with Dr Yi Zheng and staff. The care n ensuring you are comfortable and not nervous about procedure.

Absolutely 1 of the better Dr's I've ever had always proactive and not reactive. Thanks for everything read more

Dr Zheng is a great gastroenterologist and hepatologist. Took excellent care of me for my endoscopy and colonoscopy explaining all options. Good flow up after procedure with telehealth. Highly recommend this office. read more

Worst experience. spent so much time fighting payment dispute. Never go back to this doctor....

Smooth, lots of communication. Responsive . Office responses quickly to questions . Tele visits are convenient

Love Dr. Zheng. Dr Kung was also great but she is fabulous. Can't imagine seeing a different Dr.

I am very happy with Dr Zheng! I wasn't happy when Dr Kung retired, but she has stepped into his practice without missing a beat!

The entire team was very polite and respectful. They were very quick and efficient, and I would certainly recommend Dr. Zheng to anyone needing this type of care. read more

Please read the other 1 star reviews before subjecting yourself to months of frustration. I was also a prior patient of Dr Kung who was competent and honest. As it was time for my 10 year colon screening, my primary physician referred me to Dr. Zheng for the screening. As other reviews note, the billing nightmare you are likely to experience is much worse than the colonoscopy prep and procedure. A colon screening should be 100% covered by your insurance, but that is not the case if the doctor submits the claim as diagnostic rather than screening. Read the reviews and see how many people this has happened to, and good luck dealing with her office to get this corrected. They will lie and lie and lie again stating they will resubmit a corrected claim. Because of their miscoding the insurance claim you will be responsible to pay for not only the procedure, but also the anesthesiologist, pathology and the surgery center. The money grab described in other reviews is also spot on. At the end of the my procedure I stayed in the recovery room for about 30 minutes waiting for Dr Zheng to discuss the results, after which the orderly said Dr Zheng had to go to their next patient and would set up a phone call to go over the results. Sounded ok to me, but a few days after that 15 minute phone call Dr Zheng bills me $300 for the call. If this sounds like something you want to deal with for months and pay thousands out pocket for a procedure that should 100% paid by insurance, by all means make your appointment. read more

Flawless experience for a medical procedure everyone loves to hate (colonoscopy). Good communication from office through emails and texts, good instructions. On time and smooth procedure the "day of". Good followup. read more

The whole team was awesome, service was professional, great experience with this team

Dr. Zheng is so nice and very easy to talk to. She kindly answered all of my questions and but my concerns at ease.

Nice medical facility. Great staff care. Fast service. Quality care. Easy access to freeway

Dr. Zheng is a very professional gastroenterologist who truly cares about her patients. I would highly recommend her to anyone in need of a colonoscopy, you couldn't choose a better doctor. read more

called to make an appointment and was told to fill out medical information first. office staff sent info I complete it and sent back. Got a message back stating we will call you back shortly with an appointment. That was on a Thursday. No call back called Tuesday. Same office person the Dr needs to review. I said any info needed is on John Muir portal. another call a week later still no appointment and no call backs after I left 2 on voice mail. Another excuse we need a referral. New Medicare ins with secondary N plan doesn't require a referral I said read the card it states no referral needed and she can call the number on the back of the card. she again said Dr had to review 6 th phone call can never get past the front desk with this rude MA. I called back and left a message saying I'm terminating this non appointment due to their inability to take on a referred patient from our Dr. Found another one and got an appointment right away. read more

Dr Yi Zheng is a dangerous Gastroenterologist. Call for an appointment for a colonoscopy. She does not give you a pre-examination. You may have issues like IBS or Crohn's disease, but you will never know because she will not see you in person. You will get your instructions for your colonoscopy by email. Good luck with that. There are side effects that you should be aware of that could be dangerous. I got very sick on the second day of a three day cleanse and vomiting. I was running from both ends. I was weak dehydrated and sick. I called her office on the second day told them I needed to talk to her. Her staff said we will forward your message and she will call you. She never Called. I had to do this for three days drink 3 gallons of that horrible solution and take four laxatives in the morning and take four laxatives in the evening for three days in addition to the 3 gallons that I had to drink. I was never so sick in my whole life. I didn't know if I should go to the ER or not but this doctor does not care about anything about you. When I made the appointment for the colonoscopy, she gave me an appointment to come in and have a liver test. I never saw her for that liver test ultrasound. I don't even know why I had to have a liver test. And I never got any results of a liver test. But you can bet she billed my insurance. On the day that I went in for the colonoscopy and was on the table and was hooked up to an IV. I told the male nurse who was standing there to please. I need to talk to Dr. Zhang before the procedure. I could barely get in that place. I was so weak. So yes, I was very concerned.And by the way, I am a high risk patient for colon cancer and I'm 76 years old. All the women in my family have died from colon cancer. So of course I take all of this very seriously. When I asked to speak to the doctor before she started that male nurse said don't worry about it and just a couple of seconds, he says I'm going to put this in your IV and you will be out and won't remember a thing. I told him again I want to see the doctor before she begins and at that point, he injected that medication into my IV and within seconds I was knocked out. How do you do that to somebody without their permission. There's got to be some kind of log against that. When I woke up, I found out that the colonoscopy was not successful. I didn't expect it to be because I couldn't finish the cleanse, which is why I wanted to talk to her. But again she does not care. She will not discuss anything with you unless you want to repeat the process all over again and she'll be happy to schedule you for another second colonoscopy. Again, it's all about her making money. I never got to talk to her before the colonoscopy or when I had the colonoscopy or when the colon colonoscopy was over with. I never saw her. I don't even know what she looks like. Finally someone came and said the colonoscopy was not successful here are your clothes get dressed she will call you tomorrow. I said are you sure she'll call me tomorrow well, I was told if she doesn't you can call her. Yeah good luck with that. The next day she finally called and I told her what told that took on me and that there was no way I could do this process not in the way she prescribed it. There had to be another way. and she said well you can repeat the process the second time and I said no I can't. I can't complete it. She said well you know you're 76 years old and technically you don't really have to have colonoscopies anymore. I was in shock. I was oh my God are you telling me that I don't need to have colonoscopies done anymore because I'm 76 even though I'm a high risk patient and everyone in my family female has died from colon cancer that just because I'm 76 I can just forget about colonoscopies and just wait for colon cancer to come and get me. She says oh no that's not what I'm saying. I said what are you saying it sounds like you're saying I don't need to have them anymore. Just because I'm 76 well she says technically you don't if you don't want to. Do any of you people who sign up with her understand that she does not get it. That she does not understand how high risk I am and doesn't give a rip. If you go to her, you are putting your health at risk. You cannot even trust the results of any test that she gives you and know that she is giving you all the facts. and if you continue to call her, she will refuse to take your calls. This so-called doctor took on all the patients from my previous doctor Dr Kung, whom I had for years. Fabulous doctor. Always gave you pre-exams always wanted to know anything else or issues that we're going on with you before he put you on a table to do a colonoscopy. This fake doctor is so typical of people who read more