What does the area under the curve (AUC) indicate in pharmacokinetics?

The area under the curve (AUC) is a crucial pharmacokinetic parameter that quantifies the total exposure of the body to a drug over time. It represents the integral of the concentration-time graph, which shows how the concentration of a drug in the bloodstream changes after administration. The AUC provides an assessment of the drug's bioavailability, reflecting not just the amount of drug absorbed but also the duration of its presence in circulation.

When the AUC is larger, it indicates more extensive drug exposure, which can have implications for therapeutic effectiveness and safety. For example, it helps to evaluate dosing regimens and can be used to compare bioavailability between different formulations of the same medication. Understanding the AUC assists clinicians in making informed decisions about dosage adjustments and scheduling for optimal therapeutic outcomes.