The area under a curve (AUC) of metabolite concentration or drug concentration over time has biological meaning in many situations, and the test of AUC equality among a set of different dosing regimens is often of interest. For the situation where the experimental unit must be sacrificed in order to obtain an estimate of the metabolite or drug concentration, it is noted that linear combinations of mean concentrations at time points for a particular dosing regimen can be used to estimate the AUC for that regimen. Contrasts among AUC estimates are readily constructed and tested within this derivation.