Eating disorder patients often abuse laxatives in an attempt to purge excess food. Laxative abuse can cause hypokalemia and volume depletion. Hypokalemia, in turn, can lead to rhabdomyolysis. Laxative-induced hypokalemia and volume depletion have been previously reported to cause renal insufficiency, but not severe enough to require hemodialysis. A 27-year-old woman with a long history of laxative abuse presented with severe renal failure associated with hypokalemia and volume depletion. She required acute hemodialysis for worsening acidosis (pH 7.05) despite assisted ventilation. A prior episode of hypokalemic rhabdomyolysis at age 23 had resulted in only mild renal insufficiency. Her later episode of severe renal failure was linked to profound volume depletion (blood urea nitrogen 135 mg/dl). This patient calls attention to a potentially life-threatening complication of laxative abuse and indicates that volume depletion can exacerbate laxative-associated renal failure.