Relationship between the neuromuscular blocking effect of gentamicin and streptomycin and their concentration in blood.

The principle of the analysis of concentration-response relationships is valid in the case if the effective course is defined by a logistic function and the drug distribution is approximated by a two-compartment model. The method of calculation the data to construct the curves describing the dependence of the effect on drug concentration in the central and in peripheral compartments was elaborated. The relations between the concentrations of gentamicin and streptomycin and their peripheral neuromuscular blocking effect were investigated experimentally on cats. The blocking action of both drugs is evident at concentrations higher than the drug serum levels after administration of therapeutic doses, gentamicin being more active.