Evaluation of the lithium RBC/plasma ratio as a predictor of the prophylactic effect of lithium treatment in affective disorders.

62 patients with affective disorder, 31 unipolar, 22 bipolar and 9 cycloid psychotics who had received prophylactic lithium therapy for 0,3 to 7,5 years were studied. Lithium in plasma, lithium in red blood cells (RBC) and the lithium ratio (RBC/plasma) were estimated. The lithium ratio does not seem to be of predictive value in determining for which patients prophylactic lithium therapy will succeed.