Adsorption of bile acids by sucralfate, antacids, and cholestyramine in vitro

Sucralfate, one of the newer drugs shown to be effective in the treatment of peptic ulcer and esophagitis; cholestyramine, a known bile acid binder; and commercial antacid preparations of pure aluminum hydroxide, pure magnesium hydroxide, and a combination of aluminum hydroxide, magnesium hydroxide, and magnesium carbonate were tested in vitro for bile acid-binding capacity. Cholestyramine was found to be the most effective bile acid binder, with more than 90% of bile acids adsorbed at all of the pH values studied. Sucralfate proved efficacious at pH 4, 6, and 8, adsorbing about 50% of the bile acids, but its binding capacity decreased at pH 2. Pure aluminum hydroxide was the most effective of the various antacid preparations; it adsorbed about 90% of bile acids at pH 2, although this percentage was significantly reduced at pH 6 and 8. Sucralfate was significantly more effective as a bile acid absorbent at pH 4 than either the magnesium hydroxide or aluminum-magnesium hydroxide plus magnesium carbonate antacids, as effective as the aluminum hydroxide antacid, and significantly less effective than cholestyramine.