Duo Fusion™ Acid Reducer + Antacid Chewable Tablets Berry. New! From the makers of Zantac®. Famotidine 10mg/calcium carbonate 800mg. Magnesium hydroxide 165mg tablets. Dual Action™. Just 1 tablet relieves heartburn due to acid indigestion. 20 Berry Chewable Tablets. Use: Relieves heartburn associated with acid indigestion and sour stomach. Questions Call 1-888-285-9159 (English/Spanish), M-F, 8:30 - 5 EST. Boehringer Ingelheim. ©2016, BI Pharmaceuticals, Inc. All rights reserved.