Page 79 - Interactive Theoritical Notes of Bioharmaceutics and pharamcokinetics.docx compressed
P. 79
PharmD clinical pharmacy program Level 3, Semester 2 Biopharmaceutics & Pharmacokinetics (PT608(
Frequently asked questions
1. Determine the total body clearance for a drug in a 70-kg male patient. The drug
follows the kinetics of a one-compartment model and has an elimination half-life of 3
hrs with an apparent volume of distribution of 100 mL/kg.
ANSWER
K = 0.693/t½ = 0.693/ 3 = 0.231h -1
Cl = K Vd = 0.231 x (100mL/Kg. 70kg)
= 1617 mL/hr
2. Penicillin has a Cl of 15 mL/min. Calculate the elimination rate for penicillin
when the plasma drug concentration, Cp is 2 mg/mL.
ANSWER
Elimination rate = Cp xCl
2µg/mL x15mL/min
= 30µg/min
3. Why is clearance a useful pharmacokinetic parameter?
78
