7.2 : Model Approaches for Pharmacokinetic Data: Compartment Models

Compartmental analysis is a widely adopted approach to characterizing drug pharmacokinetics. It uses compartment models that conceptualize the body as a collection of reversibly communicating compartments, each representing a group of tissues exhibiting similar drug distribution characteristics. The movement rate of the drug between these compartments is typically described by first-order kinetics.

Two primary types of compartment models are recognized: mammillary and catenary. The more prevalent of the two, the mammillary model, comprises peripheral compartments characterized by low vascularity and poor perfusion linked to a central compartment such as plasma and highly perfused tissues. In contrast, the catenary model assumes a series of interconnected compartments despite its rarity in practical application, owing to its limited physiological relevance.

The simplicity, flexibility, and widespread applicability of compartment modeling enable the effective monitoring of drug concentration changes even with limited data. Nevertheless, it is important to note that different compartment models are required due to the diverse drug administration routes, reflecting the nuanced nature of drug behavior within the body.

Compartmental analysis stands as a fundamental method for describing the intricacies of drug disposition, providing valuable insights into the dynamics of drug distribution and elimination within the body.