Lithium Carbonate and Sleep in Affective Disorders

The effect of lithium carbonate on electroencephalographic sleep parameters was evaluated in six patients with affective disorders. Confirming earlier results, we report significant reductions in rapideye-movement (REM) percent and phasic-REM activity during the drug period. Doubling of delta-sleep time occurred during lithium administration, and a negative correlation between REM percent and delta percent was found; there was no immediate REM compensation in the postdrug period. We propose a model for REM suppression based on REM-cycle length and the presence or absence of REM rebound.