We describe two cases of acute renal failure (ARF) after heavy alcohol intake. Remarkable features included a few days latency period after binge drinking, acute flank pain resembling pyelonephritis, lack of rhabdomyolysis or liver injury, and concomitant intake of non-steroidal anti-inflammatory drugs (NSAIDs). Renal function improved with conservative treatment, and despite NSAIDs use, hyperkalemia was not clinically significant. Since binge drinking is common in the Western population, early recognition of this syndrome may be helpful when examining a patient with flank pain and ARF of unclear etiology.