ACTIVE INGREDIENT: Each tablet contains 20 mg of famotidine, an acid reducer for heartburn relief and heartburn prevention. Compare to the active ingredient in Maximum Strength Pepcid AC. RELIEVES HEARTBURN: This product helps to relieve heartburn due to acid indigestion and sour stomach. PREVENTS HEARTBURN: Taken 10 to 60 minutes ahead of time, Famotidine Tablets 20 mg prevents heartburn due to acid indigestion brought on by eating or drinking certain foods and beverages. JUST ONE TABLET prevents and relieves heartburn due to acid indigestion brought on by eating and drinking certain foods and beverages. This heartburn medicine lasts up to 12 hours. Use for adults and children 12 years and over. This product is gluten free. HEARTBURN MEDICINE: The active ingredient in Famotidine Tablets 20 mg is an H2-blocker, which works as an acid reducer to help relieve heartburn. Lasts up to 12 hours. Use for adults and children 12 years and over.