### INTRODUCTION

In pharmacology, you will encounter concentration-time graphs for drugs. These graphs are very useful as you can calculate several pharmacokinetic parameters from them.

One parameter that you can find directly from such a graph is the area under the concentration-time curve (AUC).

Once you know the area under the curve, you can then calculate other parameters including clearance and volume of distribution.

To find the area under the curve, you use the trapezoidal rule. This activity works through the trapezoidal rule and how to use it to find the area under the curve.