Question

1. A pharmacokinetic evaluation of the absorption and elimination of a new drug provide the following data for time (hours) and concentration (mg/L): DATA t(hr) Conc(t) vwwww 250 mg Dose 0.0833 1.00 0.1667 1.60 Vd 42 L 0.25 2.75 0.5 3.33 0.75 3.65 17.1 mg h/L AUCPO wwww.www. 1 3.50 2 2.70 Drug t 2.5 h 4 1.6500 8 0.5000 12 0.1750 250mg IV produced a Co of 5.95 mg/L with an AUCIV of 21.46 mg h/L www.wvww. From this data, estimate the following parameters: KElimination KAbsorption Tmax Cmax F

Answer 1

Dose = 250 mg

Co = 5.95 mg/L

Vd = 42 L

F(bioavailability) = 17.1/ 21.46 = 0.8

t1/2 = 0.693 * Vd/ Cl

Cl= 0.693 * 42 / 2.5 = 11.64

Kelimination = Cl/Vd

= 11.64/42 = 0.28

Cmax = 3.65

Tmax = 0.75 hour