Population pharmacokinetics of alcohol on Chinese subjects using breath measures

Alcohol is a widely used drug. Our objective was to examine alcohol pharmacokinetics in Chinese subjects through the breath measurement of blood alcohol concentration (BAC) to identify any measurable covariates that may help explain variability between subjects.

Breath-alcohol measurements of 184 healthy Chinese subjects were collected. Compartmental models including one- and two-compartment process were examined. First-order kinetics was applied to model alcohol absorption and elimination phases. For the sake of simplicity, only the subject's body weight, sex and stomach condition were investigated as covariates in our random effects modelling.

The body as a whole behaves as a single compartment, with the suggested one-compartment model being good enough to characterize the biological process. In line with other studies, food ingestion before/with the dose slowed down alcohol absorption into the central compartment. Female subjects exhibited a significantly higher BAC elimination rate than that of males. Body weight also contributed to the observed inter-subject variability in alcohol clearance.

We present a model for estimating blood-alcohol levels from breath-alcohol measurements. The results of our study are useful particularly in relation to drink-driving prosecutions because of the routine use of breath-alcohol measurements as evidence in such cases through the world.