• Frank Nemec, MD  •  Donald Kwok, MD  •  Gregory Kwok, MD
    Brent Burnette, MD  •  Travis Vickers, DO

    We have moved! Please visit our new location at:
    6950 S. Cimarron Road, Suite 200, Las Vegas, NV 89113

    As of September 11, 2019 the FDA found trace levels of N-nitrosodimethylamine (NDMA), a probable human carcinogen, in the heartburn drug, Zantac and its generic equivalent, ranitidine. NDMA is highly toxic to the liver and other organs, and is a probable human carcinogen. NDMA is an industrial by-product or waste product of several industrial processes, such as manufacturing a component of rocket fuel and water treatment by chlorination or chloramination of organic nitrogen-containing wastewater. First and foremost, the Zantac itself is very safe; however, during the manufacturing process, the drug is being contaminated with NDMA. Of note, this is the same contaminant that was recently found to have “unacceptable levels” in several popular high blood pressure medications. To put it in perspective, the European Medication Agency has estimated the lifetime risk of cancer to be extremely low (~1 in 5000) for an adult patient who had taken valsartan at its highest dose every day from 2012 – 2018. The FDA and other international drug regulators preliminary testing of Zantac have found traces of NDMA that barely exceed the amounts one would find in common foods. Therefore, the FDA has not recommended stopping Zantac at this time. Nevertheless, given that there are other options, we at Gastroenterology Associates recommend discontinuing Zantac for now and switching to Pepcid (famotidine) which is another brand of Histamine 2 blocker.

    For over two decades, Gastroenterology Associates has cared for the digestive health of Southern Nevadans. We strive to deliver compassionate, progressive medicine and an unsurpassed level of safety. Our four experienced, Board Certified physicians are dedicated to providing superior medical care for a range of digestive disorders, including conditions involving the esophagus, stomach, intestines, liver, pancreas and gallbladder. Colon cancer prevention for Las Vegas residents is at the core of what we do at Gastroenterology Associates. We welcome you to learn more about our physicians, state-of-the art, on-site surgery center and tips for ensuring your digestive health.

    Click here to see if you qualify for a free colonoscopy through AHN.

    Dr. Nemec, Dr. D. Kwok and Dr. G. Kwok were named among the best physicians in Southern Nevada! This distinguished honor is featured in the August 2013 issue of the Desert Companion.

Improving the digestive health of Southern Nevada since 1986. (702) 796-0231

Surgical Center

Gastroenterology Associates proudly operates an onsite surgical center, located with our physicians' offices on Cimarron Road. Here, we employ technologically advanced equipment as well as the medical industry's highest level of safety standards.

Our Promise

As your physician, we recognize and value the trust you’ve placed in us. We never take your health for granted. Therefore, we continually evaluate our equipment and techniques to further build upon our reputation as Southern Nevada’s most respected gastroenterology practice. Your health, your trust—our promise to you.

Honor Reform american board of internal medicine American Gastroenterological Association Desert Companion American College of Gastroenterology American Society for Gastrointestinal Endoscopy

Contact Us

Call us today at 702-796-0231 Fax: 702-796-5211


Please contact our office to schedule an appointment or should you have any questions. We’re standing by and are dedicated to your digestive health.