Plasma aluminium levels in patients on maintenance haemodialysis fall when oral aluminium hydroxide is withdrawn.

In 25 patients on maintenance haemodialysis the mean predialysis plasma aluminium level fell on two occasions when oral aluminium hydroxide was withdrawn for seven and twelve weeks. Substitution of half the prescribed dose of aluminium hydroxide with magnesium hydroxide led to a significant lowering of predialysis plasma aluminium levels over seven months, with no change in plasma phosphate levels. Oral magnesium hydroxide was associated with a mild rise in plasma magnesium levels.