The use of lithium ions in the treatment of manic states is discussed. Lithium is possibly the only specific drug treatment presently available for the major psychoses and has met with enthusiasm in England, Scandinavia, Australia and, more recently, in Canada and the United States.A number of the published papers on the subject are not sufficiently comprehensive to provide guidance for even its empiric use; some lack the necessary controls and design to permit comparisons with other studies.Some clinicians with wide experience of lithium therapy do not maintain laboratory control of patients by ordering serum lithium determinations but rely entirely on clinical judgement in establishing drug schedules. This is not advised if one has little experience with lithium therapy because of the possible side effects and toxicity.