Match each pharmacokinetic characteristic or clinical scenario to its primary effect on a drug's pharmacokinetic parameters.
- Extensive first-pass hepatic metabolismDecreases oral bioavailability
- Extensive binding to peripheral tissue proteinsIncreases apparent volume of distribution
- End-stage renal disease (for a renally excreted drug)Prolongs elimination half-life
- Co-administration with a cytochrome P450 inducerIncreases hepatic clearance
Answer
Extensive first-pass hepatic metabolism decreases oral bioavailability. Extensive binding to peripheral tissue proteins increases apparent volume of distribution. End-stage renal disease prolongs elimination half-life. Co-administration with a cytochrome P450 inducer increases hepatic clearance.
Each pharmacokinetic principle governs a specific aspect of a drug's life cycle in the body. First-pass metabolism directly limits systemic entry (bioavailability). Tissue binding pulls the drug from the measurable plasma compartment, expanding its apparent volume of distribution. Organ dysfunction (like renal failure) impairs clearance, which mathematically prolongs the half-life. Finally, enzyme induction accelerates hepatic metabolism, thereby increasing hepatic clearance.
Step-by-Step Solution
Key Concept
Core pharmacokinetic parameters (bioavailability, volume of distribution, half-life, clearance) and the clinical/physiologic factors that alter them.