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Multiple fill-in-the-blank
The pharmacokinetics of trastuzumab fit a two-compartment linear pharmacokinetic model. The estimated clearance is 0.225 L/day, volume of the central compartment is 2.95 L and the elimination half-life is long at 28.5 days.[Fill in the blank] What is the estimated volume of distribution during the elimination phase?[Fill in the blank] Is the volume of distribution during the elimination phase different to the volume of distribution of the central compartment? Why?[Fill in the blank] What is the expected initial plasma concentration in a 70 kg patient if the intravenous loading dose is 4 mg/kg?[Fill in the blank] What maintenance dose will required to maintain that plasma concentration?[Fill in the blank]
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To approach this pharmacokinetics question, I’ll break down each blank and examine the details given and the standard two-compartment model relationships.
27a) What is the estimated volume of distribution during the elimination phase?
- In a two-compartment model, the elimination-phase (β) volume of distribution Vdβ can be obtained from the relationship Vdβ = CL / ke, where ke is the elimination-rate constant. The elimination half-life t1/2β is 28.5 d......Login to view full explanationLog in for full answers
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