<p>Lanthanum Carbonate is a phosphate binder that reduces absorption of phosphate by forming insoluble Lanthanum phosphate complexes that pass through the Gl tract unabsorbed. Both serum phosphate and calcium phosphate product are reduced as a consequence of the reduced dietary phosphate absorption.<br />
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In vitro studies have shown that Lanthanum binds phosphate in the physiologically relevant pH range of 3 to 7. In simulated gastric fluid, Lanthanum binds approximately 97% of the available phosphate at pH 3-5 and 67% at pH 7, when Lanthanum is present in a two-fold molar excess to phosphate. Bile acids have not been shown to affect the phosphate binding affinity of Lanthanum. In order to bind dietary phosphate, Lanthanum Carbonate must be administered with or immediately after meals.</p>