Vecuronium is considered to be a desirable neuromuscular relaxant for patients with renal failure because its elimination depends mainly on metabolism by the liver. 1.2 Whereas some studies demonstrated that the duration of action of vecuronium was the same in patients with normal renal function and those with chronic renal failure (CRF), 3,4 others showed that the plasma clearance of vecuronium was decreased and the duration of action prolonged in CRE 5,6 Further, wide inter-patient variability exists both in patients with normal renal function 7 and in patients with CRE 8,9 Although altered responses of muscle relaxants in primary hyperpamthyroidism have CAN J ANAESTH 1995 / 42:5 / pp 395-8