Plasma and erythrocyte concentrations of lithium.

The authors have studied the clinical response, EMG and EEG changes in 12 depressed patients after 28 days of lithium carbonate treatment of 1,200 mg daily. The findings confirm: (1) a high correlation between the degree of improvement and the RBC lithium: plasma lithium ratio on the 28th day; (2) a slight decrease in motor conduction velocity (m.c.v.) and increase of M-response duration during lithium treatment; (3) no correlation between EEG and lithium levels and percentage of improvement.