Effect of aluminum hydroxide on plasma fluoride and fluoride excretion during a high fluoride intake in man

Abstract A study was carried out in man to investigate the effect of small doses of aluminum hydroxide (30 ml three times daily, containing a total of 1.8 g aluminum) on plasma fluoride levels. In control studies, a 15 mg dose of fluoride as sodium fluoride was given by mouth three times daily and plasma fluoride levels were determined 1, 2, and 4 hr after each dose. In the experimental studies an oral dose of aluminum hydroxide was given together with each dose of sodium fluoride. Plasma fluoride levels were determined at the same time intervals as in control studies. Urinary fluoride was determined on 24-hr urine collections in both study phases. Following each dose of fluoride a distinct rise and subsequent gradual fall of plasma fluoride with time was noted. Administration of aluminum hydroxide markedly decreased plasma fluoride levels at all time intervals, the average decrease being 41%. Urinary fluoride also decreased significantly, by 51%. This study has shown that relatively small doses of aluminum hydroxide significantly decrease both plasma and urinary fluoride levels.