Speth et al. [96] reported apparent volume of distribution ranging from ∼0.55 to 0.94 L/kg in adult patients. In other studies with oral or rectal exposure, apparent volumes of distribution ranged from ∼0.52 to 0.79 L/kg. In neonates, the median apparent volume of distribution is 0.96 L/kg. This indicates that propylene glycol is uniformly distributed in total body water without a significant distribution to specific tissues. The higher volume of distribution in infancy reflects the higher body water content and consequently, it is reasonable to assume a lower distribution volume in geriatric patients. It can also be predicted with certainty that propylene glycol will distribute into the water compartment of the placenta and fetus as has been demonstrated for ethanol.