DESC: INDICATIONS: MAXIMUM STRENGTH Zantac 150 reduces the production of stomach acid. This is what makes MAXIMUM STRENGTH Zantac 150 different from antacids, which neutralize the acid already in your stomach. Antacids do not reduce the production of acid. MAXIMUM STRENGTH Zantac 150 can be used for: Relief of heartburn associated with acid indigestion and sour stomach. Prevention of heartburn associated with acid indigestion and sour stomach brought on by certain foods and beverages. Free of sugar, lactose, and gluten. Can be taken with or without food. Store per label recommendations. Avoid excessive heat or humidity.