Bioavailability of lithium carbonate and lithium citrate: a comparison of two controlled-release preparations

The pharmacokinetics of two marketed controlled-release lithium preparations, lithium carbonate ('Priadel') and lithium citrate ('Litarex'), were compared in 5 normal volunteers in a crossover design using identical doses (27.2 mmol lithium). Although the total bioavailability of the two preparations was similar, the peak serum lithium achieved was significantly lower with the lithium citrate than with the lithium carbonate preparation.