The results of investigations carried out to evaluate the inhibitory activity in vitro of seven vaginal antiseptic douche solutions against several strains of vaginal lactobacilli isolated from asymptomatic women are reported. Some of the products examined showed marked antibacterial activity even at high dilutions and for short exposure times. The post-antibiotic effect of two of these antiseptics on vaginal lactobacilli was also evaluated. The results of these investigations suggest that uncontrolled use of antiseptic products could cause changes in the normal vaginal flora.