Mechanism of Action Aluminum hydroxide: Neutralizes stomach hydrocloride to form AlCl3 salt plus water- increases gastric pH Magnesium hydroxide: Promotes bowel evacuation by causing osmotic retention of fluid, which causes the colon to distend with increased peristaltic activity- forms magnesium chloride when reacts with hydrochloric acid Simethicone: Disperses and prevents gas pockets in the GI system by decreasing surface tension of gas bubles Contraindications Hypersensitivity to any component of the formulation Cautions Caution in renal failure