New aspects of clinical pharmacology of antacids.

Most antacids contain magnesium and/or aluminium hydroxide but some include also bicarbonate and calcium carbonate. The net effect of antacid action is the reduction in gastric acidity and in peptic activity but recent studies indicate that aluminium-containing antacids exhibit the cytoprotective activity or enhancement of natural mucosal defense mechanisms. This protective action has been attributed, in part, to the release of endogenous prostaglandins but other mediators such as hexa-aquo-aluminium cation and nitric oxide have also been proposed. Aluminium-containing antacids are known to accelerate the healing of chronic gastroduodenal ulcerations and this has been attributed primarily to their acid neutralizing capacity. Since antacids interact with luminal epidermal growth factor (EGF) which exhibits ulcer healing properties it has been proposed that this peptide is implicated in the healing of gastroduodenal ulcerations by these drugs.