Historically, the milk-alkali syndrome developed as an adverse reaction to the Sippy regimen of milk, cream and alkaline powders as treatment for peptic ulcer disease. The classic description includes hypercalcemia, metabolic alkalosis, and renal failure. Over the past 20 years, milk-alkali syndrome has had a resurgence, as consumption of supplements containing calcium has increased. A 46-year-old man presented to the emergency department after outpatient labs to evaluate his fatigue. He was found to have acute renal failure and hypercalcemia (total serum calcium was 15.9 mg/dL). Subsequent laboratory evaluation excluded both hyperparathyroidism and malignancy as causes. A detailed history led to the diagnosis of milk-alkali syndrome. With hydration and cessation of calcium carbonate ingestion, his renal function and serum calcium levels returned to normal. Physicians should have a high index of suspicion for milk-alkali syndrome in patients with hypercalcemia. Milk-alkali syndrome is no longer a merely a historical curiosity; it is currently the third most common cause of hypercalcemia. © 2010 Society of Hospital Medicine.