Zantac is a prescription medication that is used for upset stomachs and indigestion, gastroespohageal reflux disease and other acid build-up relief. According to Drugs.com, Zantac provides relief by lessening acid production in your stomach. One side effect of Zantac is pneumonia. Zantac is easy to take. Zantac is safe to take by pregnant women, however, Ranitidine, one of the ingredients, does affect breast milk. Place the tablets in a 6 oz. to 8 oz. glass of water and then wait for them to dissolve before consumption. It is advised to take a dose of medication as soon as you remember missing it. If it is at the time of your next dose, it is better to just take the allotted dose and not to take extra medicine to make up for a missed dose of medication. Save on a prescription of Zantac here!