[On the time course of action of nondepolarizing neuromuscular blocking drugs (author's transl)]

1. Time of onset and duration of action of various doses of pancuronium, tubocurarine, alcuronium , metocurine or dimethyltubocurarine, gallamine and fazadinium were studied by means of mechanomyograms of the hand muscles (twitch) following supramaximal electrical stimulation of the ulnar nerve (100-120 V, 0.2 ms, 0.2 Hz) in 293 patients during neurolept anaesthesia. -2. With an intravenous injection rate of about 5s there was no difference in latency time, however, the time of onset was found to be dose dependent. At equipotent conditions (ED95) the onset time correlated with the molecular weight of the muscle relaxants. -3. As expected the duration of action was dose-dependent. Following equi-effective doses (ED95) the duration of action correlated closely with the molecular weight. -4. The relation between the duration of action and the dosage of a muscle relaxant could sufficiently be described by the equation Y = a x Yb and straightened applying a double-logarithmic plot. The values of a and b for various degrees of recovery were obtained by regression analysis. Thus, the duration of action can be predicted by substituting of dose values into the above equation.