Vaginal absorption of hexachlorophene in the rat

The pharmacokinetics of hexachlorophene (HCP) was studied in sexually mature virgin Wistar rats. [14C] HCP was injected either via the femoral vein, (ivn, 0.87 or 3.87 mg/kg in saline) or into the vaginal orifice (ivg, 0.87 mg/kg in corn oil). The disappearance of 14C from the blood after ivn administration followed the kinetics of a 2 compartment open model. The blood 14C profiles were superimposable, suggesting that the distribution and elimination rate constants for both doses were similar. After ivg application of [14C] HCP, 14C was detected in tail blood at 0.5 h, peaked between 2 and 4 h and disappeared slowly to 12 h but more rapidly thereafter. Less than 10% of the ivg dose of [14C] HCP remained in the vagina after 4 h. The cumulative recoveries of 14C in the faeces and urine 5 days after ivn administration were 85% and 4.6% of the dose, respectively. Comparable recoveries following ivg administration were 72% and 3.7%. The results suggest that HCP readily penetrates through the vaginal mucosa of the rat.