Steady-state lithium blood level fluctuations in man following administration of a lithium carbonate conventional and controlled-release dosage form.

A controlled-release lithium carbonate tablet was compared to an immediate release lithium carbonate capsule in normal volunteers. These crossover studies at steady state showed that the tablet produced a smoother serum curve than the capsule with no loss of total bioavailability. Quantitatively, the capsule produced about 1.4 times more fluctuation in serum lithium values than the tablet.