Neuromuscular blocking drugs can be divided into those that are: (i) e
xcreted entirely by the kidney; (ii) predominantly by the kidney but a
lso by the liver; (iii) mainly by the liver but also by the kidney or;
(iv) removed by other metabolic pathways. Rocuronium is mainly excret
ed by the liver and pharmacokinetic and pharmacodynamic studies in hum
ans suggest that its duration of action may be prolonged to a greater
extent in patients with hepatic disease than in patients with renal di
sease. The effect is likely to be modest and not a contra-indication t
o its use.