Acute lithium intoxication is a frequent complication of chronic lithium therapy for manic depressive disorders. Because of lithium's narrow therapeutic index and widespread use, lithium intoxication remains prevalent in 1994. This review summarizes information on the renal handling of lithium and the physiologic basis for toxicity. Recent reports that describe previously unrecognized side effects of lithium intoxication are discussed. We also present management guidelines based upon our understanding of the renal handling of lithium. In this review we compare the effectiveness of lithium removal by various dialysis methods, including bicarbonate dialysis, peritoneal dialysis and continuous arteriovenous hemofiltration. Hemodialysis remains the cornerstone for the treatment of acute lithium toxicity.