The syndrome of lithium toxicity has been well described. Hemodialysis is the recommended treatment for severe toxicity. We report a case in which continuous venovenous hemodialysis was used in the treatment of lithium toxicity. The calculated average lithium clearance was 23 mL per minute, comparing favorably with that of normal renal clearance (20-30 mL/min) and of intermittent hemodialysis (50-100 mL/min). This report discusses the potential benefits of this therapy in a hemodynamically unstable patient who may not tolerate hemodialysis.