Half-Life and Clearance · Pharmacology

What is the mathematical relationship between Half-life ($t_{1/2}$), Volume of Distribution ($Vd$), and Clearance ($Cl$)?

$t_{1/2} = 0.693 \times (Vd / Cl)$
$t_{1/2} = 0.693 \times (Cl / Vd)$
$t_{1/2} = Vd + Cl$
$t_{1/2} = 1 / (Vd \times Cl)$

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Correct answer: $t_{1/2} = 0.693 \times (Vd / Cl)$

The half-life is directly proportional to the volume of distribution and inversely proportional to clearance. This means that an increase in $Vd$ or a decrease in $Cl$ will prolong the drug's half-life.

Difficulty: Medium Question 4 of 20

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