Compare to Maximum Strength Pepcid AC active ingredient. Just one tablet of Member’s Mark™ Acid-Pep Famotidine Tablets, 20 mg prevents and relieves heartburn associated with acid indigestion brought on by eating and drinking certain foods and beverages. This maximum strength heartburn medicine is intended for adults and children 12 years and over. Helps prevent meal-induced heartburn when taken at least 10-60 minutes before eating. Lasts up to 12 hours.