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Qualifications and Experience
Awards and Publications
Dr. Mark Johnson received his undergraduate degree from the University of Washington. He attended medical school at George Washington University.
Dr. Johnson then completed his residency in internal medicine at LAC-USC Medical Center; in addition he was a chief resident there. His postgraduate training continued at the University of California at Irvine with the completion of an additional two years of fellowship specializing in gastroenterology.
He is board certified by the American Board of Internal Medicine as well as the specialty of Gastroenterology. Dr. Johnson is a member of several professional societies including the American Gastroenterology Association, the American College of Gastroenterology and the American Society of Gastrointestinal Endoscopy.
He has been in private practice since 1989.
Verified Patient Reviews
I found my visit to his office to be the most pleasant experiences I've ever had with any doctor ever in my lifetime.im actually looking forward to my next visit.
Small and quiet office. I did not have to wait at all. The doctor himself called me in. Very quick and easy and his bedside manner was great. I wish all doctors could be like Dr. Johnson!
Very polite and attentive doctor.
Great doctor, no nonsense, very knowledgeable with excellent bedside manners
Had a great experience with Dr. Johnson on my first visit. He is a great listener, asks thoughtful questions and appreciates patients who are knowledgeable about their own condition. He did not just order a bunch of tests blindly, but actually advised on the most prudent course of action given my situation. I really enjoyed the conversation and look forward to returning for a followup visit!
Dr. Johnson was very kind and did a complete assessment of my symptoms. He was careful to explain the process he would follow in making a diagnosis. I appreciated his thoughtfulness and friendly demeanor.
He order the correct testing and diagnosed my very quickly. Due to his ordering and diagnosing, he kept me from getting very sick so thank you.
I highly recommend Dr. Johnson. He's the Best of the best. He really put my mind at ease.
Dr. Johnson is at the top of his field in his profession. He is very easy going and reassuring . It was a pleasure to meet with him and work on my medical situation.
He was thorough, such a great listener, validated my concerns and assured me that he would attentively help me. I feel in good hands.
Professional,courteous , caring ,respectful
Excellent Dr.! Very friendly, knowledgeable and attentive. Listened intently to everything I had to say. I would highly recommend Dr. Johnson.
Dr. Johnson was great. Highly recommend him. Scheduling was easy, prompt and you never felt rushed. Thanks Dr!
He never contacted me with my lab results. He had 5 vials of my blood taken, to test me for a few things & I never heard back from him. Waste of a trip, time & waste of my health insurance.
Sorry I have the wrong coverage to use ZocDoc.
Staff was rude and incorrectly scheduled my endoscopy so I went to the hospital, only to find out that she had forgotten to schedule it. The doctor was unable to find anything, and said it was all in my head. Luckily, he gave me pictures of my endoscopy- the moment I showed them to my ENT doctor he was able to diagnose me. Do not go to this man. Even my ENT told me that he had heard bad things about this doctor, that he no longer cares.
Very pleasant. Listened to what I had to say. Explained his thoughts so I was able to understand his treatment.
Dr. Johnson is a wonderful doctor and a great staff. Colonoscopy went so smoothly. Felt just fine after pocedure.
I hope Doctor Mark Johnson will help me with my GL problems.
He spent the time with me and made sure I got all my questions answered. He was also very knowledgable of my condition
I felt very uncomfortable throughout the entire appointment. He didn't seem to want to run preliminary test, just jump to the most extreme procedure. I feel like preliminary tests have to be run to ensure which procedure is correct.
Great doctor. Definitely recommend him!
Dr. Johnson was very compassionate and listened to my information and worries. I did not feel rushed like I have in previous appointments with other physicians, and the environment in his office was very clean and calm.
Dr. Johnson was very nice.