Lanthanum Carbonate

Absorption

Bioavailability very low (<0.002%) following single or multiple dose oral administration.

Toxicity

The symptoms associated with overdose are adverse reactions such as headache, nausea and vomiting. Lanthanum carbonate was not acutely toxic in animals by the oral route. No deaths and no adverse effects occurred in mice, rats or dogs after single oral doses of 2000 mg/kg.

The Uses of Lanthanum Carbonate

Treatment of hyperphosphatae mia in patients with end stage renal disease.

Background

Lanthanum carbonate is a phosphate binder commonly used in clinical practice. It is marketed under the trade name Fosrenol by Shire Pharmaceuticals. It is the largest of all pills filled in community pharmacies. Sometimes patients forget that Fosrenol is not swallowed whole, but instead should be chewed. This has led to severe choking. It is prescribed for treating high phosphate levels, mainly found in patients with chronic kidney disease. Lanthanum should be taken with meals and binds to phosphate in the diet, preventing phosphate absorption in the intestine.

Indications

Used to reduce serum phosphate in patients with end stage renal disease (ESRD).

brand name

Fosrenol (Shire).

Flammability and Explosibility

Not classified

Pharmacokinetics

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.

Metabolism

Lanthanum is not metabolized.