I have been seeing Dr. Zlock and his staff since La Casa Via, handling my diabetes since I was diagnosed with Type II in High School. While we haven't successfully eradicated my diabetes, which whole-heartedly, is an issue with my own discipline than anything else, Dr. Zlock has been with me every step of the way. He keeps logs of his patients, not just on their diabetes journey, but their life Journey, and a Doctor willing to do that, is a Doctor who cares. So he knows about my employment journey, my post grad work, and current work, I walk in, and it's like catching up. We have worked through our medications, and we have seen that when I am determined, ie: Exercising and Dieting, low carb, calorie deficit, higher protein, my a1c goes back down to a good range, my Triglycerides and cholesterol get within check, and all my vitals look good. However it's hard to stay motivated like that, and I fall off, and Dr. Zlock is there to mix up my medication, and let me know that I've gotta try harder, or the perils of Diabetes will catch up to me. I have always had good relations with the staff, never any problems. I get in, their nice, vitals checked, good catching up, I call in for medication updates or prescriptions, and they get to it promptly. Sonya (sonja? spellign please?) has always been there to figure out my logistics. All in all, I cannot recommend Dr. Zlock and his staff enough. If you are in the need for a modern day Endocrinologist.... this man, is THE MAN. read more

Douglas Zlock is a very very good doctor. My 87-year-old father, a retired physician, has been seeing him for multiple health issues, and he has been knowledgeable, courteous, and informative at all of our office visits. Obviously Dr. Zlock has a great deal of experience, and both myself and my father are appreciative of his level of expertise. His staff, however, are a different matter altogether. It is disconcerting to call in about a prescription 2 months after a visit, and the staff can't find a record of it, and when they do (hours later) they insist they must call Dr. Zlock to confirm it. He's prescribing insulin, for godsake, not Class I narcotics. Plus the doctor works in the John Muir Health network, where everything is painstakingly documented -- even I can read the doctor's comments from the last visit online. How can his office staff possibly not know the end result of my dad's last visit? Unbelievable. So I give Dr Zlock a great review, but I have to temper it with a very real concern about the effectiveness of his staff. Put somebody in charge there who has a clue about patient care! read more

I generally try to avoid anything that sounds like overdrawn superlatives when making objective appraisals, but quite honestly Dr. Zlock may be the best doctor I've ever seen in terms of bedside manner and competence. And considering my somewhat borderline hypochondria, and probable serial abuse of a fairly good PPO plan, that's saying a lot (i.e. from John Muir to Sutter, to Alta Bates,to UCSF, to Stanford, I've seen a lot of doctors). Dr. Zlock was both informed and attentive. Like an accidental encounter with some rare animal, he was actually concerned while listening, and committed to getting to the bottom of my problems. He listened carefully and made notes on a laundry list of problems that most primary doctors would have given up on. When I was finally done neurotically citing a litany of perceived maladies and a few real conditions, he offered measured and conservative advice, ordered a blood test for a few things related to my actual diagnosed problems, and threw in a few practical tips that empowered me to improve my own health in several ways. My only complaint was that he couldn't accept tips. If you're in the East Bay with an endocrinology issue, don't hesitate to look him up. read more

Tried making an appt. I have insurance where I don't need a referral but when i called the office I was told I did. So after some back and forth and wasted time ..come to find out which I wasn't told that no I don't need a referral they take my insurance and it's just their office policy. So went with another office that was easier to deal with. read more

Quite simply the best endocrinologist in the East Bay. It is completely safe and rational to assume the extremely poor reviews below have been posted by eccentric whiners & individuals projecting themselves as sanctimonious know-it-alls... It is impossible to imagine Dr. Zlock ever raising his voice. Interesting that no one thinks, "Meh, he's 'okay'...". Dottore Zee has provided professionalism and medical insight to me for over TWENTY years and he has been absolutely instrumental enabling me to control a chronic condition that - like some of the posters here - is a tremendous pain in the ass to manage: Type I Diabetes Mellitus. I agree with the cross-country biker: Zlock is The Man. A patient listener with an open mind he, incorporates my objectives as a patient with flexible treatment regiments that have allowed me to thrive. Now, I honestly worry about that fact that at some point over the next 15 - 20 years he may actually want to retire... but I don't ever want another doctor! read more

Got a referral from my primary care physician for Dr Zlock in November 2013. When making an appointment, I was told by staff i had to go through a "review process" to be accepted as a new patient. It was the holidays so i gave it a chance. In late January they left a message on my voicemail saying i was accepted and to make an appointment. After over a month of phone tag, I finally reached someone, and the earliest they could see me was mid-May. Um, no. If I have to wait 6 months to get an appointment, I don't trust you or John Muir with my healthcare. That is demonstrably NON HEALTHCARE. Both of you are fired. read more

I have never been so frustrated with a doctor and his staff. I saw him for the first time in March 2014 and he was fairly nice and seemed thorough - I was happy with the visit and I was going to continue to see him. When I went to fill my prescription, I come to find out that he wrote down my previous prescription wrong and prescribed me the wrong dose. I had blood work done about a month ago and he said that my dose should remain the same, however, when I questioned it - he said to go ahead and just give me the lower dose. Has my blood work even been looked at?? I called numerous times in a week, but to deal with rude staff and no answered questions. I communicated that I am nearly out of pills and here I sit again with no call back on what dose I should be on based on my lab results. I will be notifying the proper channels because this is unacceptable. read more

This review is exclusively for the office staff....not Dr. Zlock. He may be the most wonderful doctor in the world, but you'll have to deal with the Stygian Witches to find out. The office staff are TERRIBLE. First of all, good luck getting an appointment. They completely discourage you from even trying to schedule there! The woman who answered the phone gave me about ten reasons why they couldn't schedule me. When I shot down each of her negative remarks, she finally sighed and said I'd have to get a referral...even though my insurance clearly states that I don't need a referral to see a specialist. Again, she starts offering me the names and numbers of other endocrinologists. She tells me I should call them, because she probably can't give me an appointment for 4-5 months anyway. When I say I'm still interested, she sighs again...loudly...and finally gives me the information I need to schedule an appointment. I tell her I'll send all the info over right away so we can schedule, and she tells me not to call back to confirm that they've received my documents, she says someone will call me. Thanks, but no thanks. I hope the doctor or someone who knows him will read this and let him know that his office staff are horribly rude, completely uncaring, unhelpful, discouraging, and negative. If he's as kind a doctor as other reviews have stated, he deserves to be better represented. On the other hand, if he approves of his staffs' treatment of patients and potential patients, I'd rather not schedule with him anyway. read more

We were so fortunate to find Dr. Zlock 18 years ago. He has taken care of both my mother and father with such grace, kindness, professionalism and competence. He is so kind and generous with his time, always responsive to my questions and concerns. His staff is courteous and follows up quickly to my requests. We couldn't ask for a better doctor! Janet R. read more

I'm a hospital RN and have worked with Dr. Zlock for years- some of the reviews here do not describe the doctor I have come to know and respect. He is extremely knowledgeable, caring, patient and one of the most competent physicians I have ever had the pleasure to work with. The reviews calling him egotistical? Wow - that is NOT an accurate description. I wont comment on his office staff as that is not something I have experience with, but if you are looking for an endocrinologist, please don't hesitate to go to Zlock, the man is the best in his field. read more

Dr Zlock had been my doctor for about 20 years, and he is wonderful!!!!!!! I have a complicated health picture, and he has always given me great care and superb advice. I find Dr Zlock compassionate and caring. Dr Zlock listens to my concerns, answers my questions, and has done an excellent job of getting things approved by my insurance. I have had interaction with a lot of doctors and offices over the years, and Dr Zlock has been an outstanding member of my support team. Yes, it can take some time to book an appointment, that's just because he is good and he is busy. If I could I would give him 10 stars. read more

I am writing this review because, prior to specializing, Dr. Zlock was my long-time primary care physician. It's surreal to me to see these negative reviews; they do not describe the man that I met with on many occasions over several years. I was always very happy with our relationship, and with my medical treatments and the testing that he authorized. Dr. Zlock was always respectful to me. He consistently listened to me, whether I had a question or concern. He was very open to my opinion regarding treatments, and he always demonstrated trust in me. He often called me at home, to follow up and make sure things were going okay. He's a very cool guy too. His moods were consistently positive, and he never offended me in any regard. He's both a man's man, and a ladies man. ;) From: (the guy who crossed the continental USA solo on his mountain bike, and developed serious digestive problems just prior to when you switched to internal medicine) . Thanks, Dr. Doug! read more

I have seen Dr. Zlock for nearly twenty years and I have absolute faith in him. He has managed my diabetes competently and professionally. He has that special touch in recommending what I should do to cope with the disease without being overbearing. He is always friendly and polite and never rushes me. I cannot speak highly enough of him. read more

Dr. Zlock has great bedside manner, looks at me when we speak, is patient, caring, sincere, knowledgeable and very competent.. His staff, in particular Sonja, are great to deal with. Thank you Dr. Zlock and your staff. read more

The complaints others have made below also ring true for me. He was my endocrinologist when I lived in Pleasant Hill. He is egotistical and passive-aggressive and will go from being very calm (almost overly so) to getting extremely uppity and angry when you ask any questions. The term someone uses of unprofessional paternalist egotist is precisely true. One of his office staff was extremely rude to me when I had called, Some of his office staff can be rude and unprofessional in this ridiculously busy practice (and why it is so busy baffles me). I mentioned a concern about this to Zlock, and he completely freaked out - started yelling and screaming at me, and told me that I needed to find a new doctor (after seeing him for several years) because I was questioning the actions of his employees. Now I understand why the staff is rude - because they are allowed to abuse patients just like Zlock. His behavior can only be described as shocking. As soon as I did get a new endocrinologist, I was diagnosed with Diabetes mellitus - something he completely missed and never treated, so his competence as a physician is highly questionable to me. read more

This review is not for Dr. Zlock because unfortunately, I never got to see him. The front desk staff is extremely frustrating. Trying to make an appointment is like pulling teeth. I called multiple times last week and was given the run around by probably 3 different people. I was told he was scheduling appointments for October 23. When I inquired with another woman, I was told I would get my appointment based off of how serious the staff thought my medical issue was. If I'm a new patient being sent to an endocrinologist from my primary care physician, it shouldn't matter. I was told the October appointment was for current patients, and that they would schedule me for December. It didn't stop there. They said they would call me back to make my appointment for me within a week. How does this make sense? I am happy to say that I have been given an appointment within the month at UCSF. How hard can customer service be? I would definitely look elsewhere before wasting your time trying to get an appointment in this office! read more

Tried for almost 3 months to get an appointment. After being on hold for an eternity, I spoke with several staff members who promised to call me back but never did. They also told me they were taking down all of my information yet every time I spoke to someone new, they had no idea what I was talking about. Finally got through months later and was told the doctor was not accepting any new clients. read more

I felt I had to give Dr. Zlock a review after seeing the one from W.J. I'm quite shocked of WJ's assessment b/c that's not the dr. that I know. I've been going to Dr. Zlock from years and I switched from a previous dr. and I haven't looked back. He spends the time, listens to your concerns and takes your point of view into consideration when prescribing treatment. He doesn't push or try to coerce you to do his treatment. I've always been more conservative and don't really believe in taking drugs or undergo surgery unless it's absolutely necessary. He's been supportive of my decision and my condition continues to improve. read more

Unprofessional paternalistic egotist. I saw Dr. Zlock after another MD diagnosed and successfully treated me for a rare metabolic condition. Dr. Zlock sarcastically criticized my prior MD and dismissed his diagnosis but provided no rationale and did no tests to confirm or refute it. He continued the treatment the other doctor prescribed and asked if I have MedicAlert to notify paramedics of the condition he says I don't have (CYA?). He handed me a patient instruction sheet but, when questioned, told me none of the instructions were appropriate. At the end he complained about the amount of time he spent with me. Criticizing other physicians may boost Zlock's ego but it does nothing for patient care. read more

Like Elaine, I've been going to Dr. Zlock for years and think he's great. He's patient, he explains, he listens. There's something very wrong with WJ's comments -- I think their condition is mental, not physical. read more

I too have been seeing Dr. Zlock for a good many years, 10 or more and find him very easy to talk to, he listens intently as well as giving me as much time as I need. I have undergone a few procedures for my thyroid and have been very happy with the care I have received. WJ appears to be angry with the world since all her other posts give low scores. read more

I have been a patient of Dr. Zlock for almost 8 years for a thyroid condition and I can honestly say that I have never met nor, could hope to meet, a kinder, more respectful, intelligent, talented doctor who is a a wonderful caring human being as well, If I could give him more than five stars, I definitely would. His patience and intelligence in treating my condition has allowed me to forego surgery. Very few other endocrinologists would have cared enough or even had the patience to monitor my condition in a consistently caring and gentle manner. Because of Dr. Zlock, I got to keep my thyrroid gland while the doctor who treated me before had neither the compassion nor the tolerance to treat me. She just wanted to nuke my thyroid. Dr. Zlock did not judge me, he just had enough respect for what I wanted and helped me to achieve it. Now that's a great doctor, I think the few negative reviews on this site from a few years back are either bogus or just misguided. Dr, Zlock is not capable of the kind of terrible behavior he has been accused of. He's the best kind of doctor, one that listens.... and cares. Be very skeptical of dramatically bad reviews of Dr. Zlock and consider the source . . . . read more