Lithium prophylaxis and interepisode mood. A prospective longitudinal comparison of euthymic bipolars and non-patient controls.

The mood stabilizing effect of lithium prophylaxis was investigated in a longitudinal design. Eighteen euthymic bipolar outpatients using lithium and 20 non-patient controls completed 13 weekly mood ratings. Groups did not differ in biographical characteristics and pre-test manic and depressive symptomatology. Apart from a higher mean happiness rating in the patient group, no statistically significant differences were found on most mood scores between groups, nor was there a group difference in variability over time. It is concluded that lithium prophylaxis does not have an extreme mood normalizing effect in well-controlled bipolars.