[Gentamicin toxicity to animals of both sexes and different ages]

Gentamycin acute toxicity in sexually-immature and sexually-mature male and female rats was tested comparatively. DL50 for the female sexually-mature rats was found to be statistically reliable lower than that for the remaining three groups of animals. The greatest differences were observed in the values for the maximum non-lethal and minimum lethal doses of this antibiotic. The authors suggeste the use of a new index for the evaluation of gentamycin acute toxicity called Dose Range Index.