The effect of lithium carbonate on affect, mood, and personality of normal subjects.

Data reflecting affect, mood, and personality attributes of 23 normal men were compared after two weeks of placebo administration and two weeks of therapeutic serum lithium levels (mean, 0.91 mEq/liter). The study was a placebo-controlled, split-half crossover, double-blind design. Affect and mood were measured by three self-rating instruments, independent rater observation, and by the subjects' "significant others." Two personality inventories were administered. Substantial affect and mood changes are induced by lithium carbonate. Lethargy, dysphoria, a loss of interest in interacting with others and the environment, and a state of increased mental confusion were reported. No generalized effects were found in the responses to ther personality inventories.