title: Assessment of antacid characteristics of drugs containing a combination of aluminium and magnesium salts using the "artificial stomach" model.
abstract: Antacid characteristics of three drugs containing aluminium and magnesium salts (combination of clay with aluminium and magnesium hydroxides, aluminium and magnesium hydroxide mixture and hydrotalcite) have been studied in a dynamic situation simulated by the "artificial stomach" model, simultaneously taking into account both gastric fluxes, a constant secretory flux and variable emptying fluxes. Therapeutic doses of the drugs were added 1. to 100 ml of 0.1 N HCl, without or with 1% or 5% meat extract, and 2. 100 ml of pooled human gastric juice (96 mmol/l, pH 1.1). In addition, antacid activity of 0.5 g aluminium and magnesium hydroxides, taken alone or in combination, were evaluated when added to 100 ml of 0.1 N HCl. In aqueous HCl solution or in human gastric juice, the three antacid drugs exhibited 1. a neutralising activity characterised by pH-rise and 2. a buffering capacity close to pH 3.8. In addition, hydrotalcite exhibited also buffering capacity at pH 1.2. The antacid-induced capacity, expressed as H+ mmol, to recover initial pH were very similar, indicating that antacid physiochemical properties are similar in HCl solution or in gastric juice. H+ consumption depended upon emptying fluxes. The same antacid characteristics were observed when antacids were mixed with 1% meat extract while 5% meat extract resulted in a modification of antacid characteristics. Therefore the antacid capacities of respective mixtures were of smaller magnitude (50-60%) than the sum of the activities of antacids plus meat extracts.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: INSERM U 10, Hôpital Bichat, Paris, France.
authors.forename: J
authors.initials: J
authors.lastname: Vatier
authors.forename: M T
authors.initials: MT
authors.lastname: Vitre
authors.forename: F
authors.initials: F
authors.lastname: Lionnet
authors.forename: C
authors.initials: C
authors.lastname: Poitevin
authors.forename: M
authors.initials: M
authors.lastname: Mignon
mesh_terms: D000536:Aluminum Hydroxide / Q000494:pharmacology*; D000818:Animals; D000863:Antacids / Q000494:pharmacology*; D004338:Drug Combinations / Q000494:pharmacology; D005746:Gastric Emptying / Q000187:drug effects; D005750:Gastric Juice / Q000187:drug effects / Q000378:metabolism; D006851:Hydrochloric Acid; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000494:pharmacology*; D008276:Magnesium Hydroxide / Q000494:pharmacology*; D008460:Meat / Q000032:analysis; D008954:Models, Biological; D013270:Stomach / Q000187:drug effects / Q000502:physiology*
chemical_list: D000863:Antacids; D004338:Drug Combinations; C010467:hydrotalcite; C013591:aluminum hydroxide, magnesium hydroxide, drug combination; D000536:Aluminum Hydroxide; D008274:Magnesium; D008276:Magnesium Hydroxide; D006851:Hydrochloric Acid