In a patient with end-stage renal disease, the clearance of a kidney-excreted drug decreases while the volume of distribution remains the same. What happens to the drug's half-life?
Show answer and explanation
Correct answer: The half-life increases
According to the formula $t_{1/2} = 0.693 \times Vd / Cl$, if clearance ($Cl$) decreases in the denominator, the resulting half-life ($t_{1/2}$) must increase. This necessitates lower doses or longer intervals to avoid toxicity.
Keep practicing
More Half-Life and Clearance questions
- Which of the following describes 'Zero-Order Kinetics' regarding drug elimination?
- A drug has a half-life of 6 hours. If the plasma concentration is currently 100 mg/L, what will the concentration be after 18 hours, assumi…
- What is the 'Extraction Ratio' ($ER$) of an organ like the liver?
- If the dosing rate of a drug is doubled during a continuous IV infusion, what happens to the steady-state plasma concentration ($Css$)?
- Which of the following would lead to an increase in the Volume of Distribution ($Vd$) and a subsequent increase in half-life?
- The 'Maintenance Dose' of a drug is primarily determined by which pharmacokinetic parameter?