Atracurium was given to 30 patients with terminal chronic renal insufficiency, in two regimens. Group I (20 patients) received a single dose of 0.6 mg kg-1 and group II (10 patients), received one or several injections of 0.2 mg kg-1. Tracheal intubation was performed with ease in all patients 3 min after the injection of atracurium. A supramaximal stimulus was applied to the ulnar nerve at wrist level, and thumb adduction force was recorded. Muscular blockade was 100% in 29/30 patients and 95% in one. Mean time between atracurium injection and reappearance of 25% of the initial muscular power (HT25) was 49 min. The recovery time index (IR25-75) was 12 min and did not increase after re-injection. No side-effects were observed and no significant differences in any of the measurements made were seen between the two groups.