Differences in plasma and tissue aluminum concentrations due to different aluminum-containing drugs in patients with renal insufficiency and with normal renal function.

The gastrointestinal absorption of aluminum from orally administered aluminum-containing drugs is well documented. Retention of the absorbed aluminum leads to elevated levels of this metal in the tissue of patients with renal failure. We studied two groups of dialysis patients who had received equal amounts of the different aluminum-containing phosphate-binders Aludrox and Antiphosphat. It has recently been shown that Antiphosphat releases only a few aluminum ions in an environment of low pH. Consistent with this finding, we found the aluminum levels to be significantly higher in the plasma, bone, and hair of patients who had received Aludrox as phosphate binder. Subjects with normal renal function excreted most of the ingested and absorbed aluminum. No data are available concerning the tissue load of the element in these subjects. We studied two groups of patients with normal renal function who had received antacid drugs prior to neurosurgery on a brain tumor. The first group of patients were treated with an aluminum-rich antacid (Maalox 70); the other group received an aluminum-poor drug (magaldrate) for 10 days prior to the operation. Analysis of the brain-tissue removed revealed twofold higher aluminum levels in the patients who had received Maalox 70. These results indicate that administration of aluminum-containing drugs leads to a tissue load of aluminum in patients with an impaired renal function as well as in those with a normal function. The extent of the aluminum load depends on the aluminum content and the liberation rate of the drug.