Analgesic nephropathy. Clinical course after withdrawal of phenacetin.

Of 14 patients with analgesic nephropathy 11 were followed up for 9 to 88 (mean 36) months after withdrawal of analgesics containing phenacetin. Ten of these 11 are still alive and have improving, static, or very slowly declining renal function. Analgesic withdrawal is therefore worth achieving even in the presence of advanced renal failure. Careful prolonged follow-up is required to prevent or detect relapse and to deal with the complications of prolonged renal failure, particularly bone disease and acidosis.Early diagnosis is life-saving in this condition. Attention is drawn to the diagnostic value of sterile pyuria, but the best screening test for the condition is careful interrogation of all patients with chronic renal disease of unknown aetiology; analgesic intake is rarely denied if asked for specifically.