Evaluation of two lithium carbonate formulations.

An open, two-way crossover study of Latin-square design was used to compare the bioavailability of a new capsular formulation of lithium carbonate, Pfi-Lithium (Pfipharmecs Division, Pfizer, Inc.), with that of standard capsular formulation, Eskalith (Smith Kline & French Laboratories). Eighteen healthy, adult male volunteers received both formulations in a randomly determined order. After administration of each 300-mg dose of lithium carbonate, serial blood specimens were obtained. Data obtained from these specimens were subjected to pharmacokinetic evaluation. There were no significant differences (p less than 0.05) in peak plasma concentration, time to peak plasma concentration, and area under the plasma concentration-time curve. These single-dose suggested that the two formulations were bioequivalent.