Neurotoxicity of topically applied hexachlorophene in the young rat

Young rats 6 to 22 days of age are extremely susceptible to the neurotoxic effects of hexachlorophene given as a daily bath of undiluted antiseptic detergent containing 3% hexachlorophene (pHiso-Hex). At this age, most rats are clinically and histologically damaged by as few as two daily baths. Younger rats are relatively resistant, probably because they have less myelin to be affected; older rats cannot be poisoned by this route, probably because the more mature liver excretes the drug more effectively. Age-dose-response curves in rats are similar to those in humans. This experimental model is potentially useful in defining other characteristics of this drug.