Antipeptic activity of antacids

Abstract

suMMARY An in vitro experiment based on the digestion of haemoglobin with pepsin was carried out to test the claim made by some manufacturers that the antacids used in their proprietary preparations had an intrinsic antipeptic activity independent of the change brought about by alteration of pH. In no case could these claims be substantiated.Antacids have played a traditional role in the treatment of peptic ulcer. Though there is no convincing proof to show that they increase the rate of healing, there is little doubt about their clinical effect of relieving the pain of peptic ulceration.The antacids in common use are calcium carbonate, sodium bicarbonate, aluminium hydroxide, magnesium oxide carbonate and trisilate, and bismuth aluminium carbonate. These are marketed under proprietary names either in combination with each other or with sedatives and anticholinergics.A perusal of the literature put out by drug manufacturers reveals that five methods of action have been claimed for antacids: they (1) diminish the quantity of hydrochloric acid in the stomach by direct neutralization, buffering of gastric acid, or absorption of H ions; (2) mechanically protect the floor of an ulcer by forming a coating on its surface; (3) stimulate mucus production which protects the ulcer; (4) absorb some of the pepsin; and (5) have an intrinsic antipeptic activity independent of alteration inpH.The investigation was undertaken to find out whether antacids have any antipeptic activity apart from that produced by alteration of the pH. Material and MethodsAnson and Mirsky (1953) described a chemical method of evaluating pepsin activity dependent on the photometric estimation of tyrosine which is split off haemoglobin after incubation with pepsin.We use a modification of this test. Two ml of bovine haemoglobin (supplied by Armour Ltd) is adjusted to a pH of 2 and incubated with 1 ml of a 0.2% of swine pepsin mixture (supplied by John

Antacids revisited: review on contemporary facts and relevance for self-management

“…In 1971, an in vitro experiment by Kuruvilla revealed high anti-peptic activity (82% and 81%, respectively) for both magnesium carbonate and calcium carbonate. 61 In addition, aluminum and calcium antacids appear to adsorb pepsin and reduce its activity more strongly than would be predicted by pH changes alone. 62 Antacids such as magnesium and aluminum hydroxide can bind to bile salts, but magnesium hydroxide binds (approximately 45 mEq/h) is secreted across the apical membrane of the stomach through a proton pump (H þ /K þ ATPase) after meal consumption.…”

Onset of acid-neutralizing action of a calcium/magnesium carbonate-based antacid using an artificial stomach model: an in vitro evaluation

“…After administration of Rennie in our study, the activity of pepsin was reduced both within the first 5 min and over the longer term (2 h). In vitro assessment has indicated that both calcium carbonate and magnesium carbonate have high anti-peptic activity (82% and 82%, respectively) [ 7 ].…”