Gastracid Suspension is used for Acid indigestion, Increases water in the intestines, Upset stomach, Sour stomach, Heartburn, Calcium supplementation, Overdose, Toxicity, Stomach acid, Painful pressure and other conditions. Gastracid Suspension may also be used for purposes not listed in this medication guide. Gastracid Suspension contains Calcium Carbonate, Magnesium Hydroxide, Magnesium Trisilicate and Simethicone as active ingredients. Gastracid Suspension works by neutralizing acids thus relieving acid reflux; neutralizing acid in the stomach; neutralizing the acid in the stomach; acting on inner lining of intestine and allowing gas bubbles to come together;