ACIPEP

Aluminium hydroxide is a slow-acting antacid. It is used to provide symptomatic relief in gastric hyperacidity. In addition, the antipeptic and demulcent activity of aluminium hydroxide helps to protect inflamed gastric mucosa against further irritation by gastric secretions.

Magnesium hydroxide is practically insoluble in water and solution is not effected until the hydroxide reacts with hydrochloric acid in the stomach to form magnesium chloride. Its neutralising action is almost equal to that of sodium bicarbonate. When the dose is in excess of that required to neutralise the acid the intragastric pH may reach pH 8 or 9. Acid rebound following magnesium hydroxide is clinically insignificant. Magnesium hydroxide has an indirect cathartic effect resulting from water retention in the intestinal lumen.

Alginic acid is a polysaccharide distributed widely in the cell walls of brown algae which is hydrophilic and forms a viscous gum when hydrated. Its salts with metals such as sodium and calcium are known as alginates. It is a significant component of the biofilms produced by the bacterium Pseudomonas aeruginosa, a major pathogen found in the lungs of some people who have cystic fibrosis. The biofilm and P. aeruginosa have a high resistance to antibiotics and are susceptible to inhibition by macrophages.

Simethicone is a chemically inert, non-systemic gastric defoaming agent that works by altering the elasticity of interfaces of mucus-embedded bubbles in the gastrointestinal tract. The gas bubbles are thus broken down or coalesced and in this form gas is more easily eliminated through eructation or passing flatus.