Pharmacrystal

www.pharmacrystalniper.blogspot.com

www.pharmacrystalniper.blogspot.com

17

– Pharmacokinetics: Principles of Eliminations

1.1) One liter contains 1,000 mg of a drug. After one hour, 900 mg of the drug remains.
What is the clearance?
        a) 100 mL
        b) 100 mL/hr
        c) 1 mg/ml
        d) 100 mg
        e) 1 mg/sec

1.2) To maintain a drug concentration at steady state, the dosing rate should equal the
elimination rate. Which of the following is true? (CL = Drug Clearance)
        a) Dosing rate = CL + target concentration
        b) Dosing rate = CL - target concentration
        c) Dosing rate = CL * target concentration
        d) Dosing rate = CL / target concentration

1.3) Which of the following is most useful in determining the rate of elimination of a
drug, in general?
        a) Drug concentration in urine (renal elimination)
        b) Drug concentration in stool (bilary elimination)
        c) Drug concentration in blood
        d) Drug concentration in brain

e) Drug oxidation rate

2.1) For first-order drug elimination, half-life t(1/2) is ____ at two places on the curve
and a constant ____ is lost per unit time.
         a) Equal; Amount
         b) Equal; Percentage
         c) Not equal; Amount
         d) Not equal; Percentage

2.2) For first-order drug elimination, given the half-life equation of t(1/2) = (0.693 * Vd)
/ CL, how many half-lives would be necessary to reach steady state (

≈95%) without a

loading dose?
         a) 1 to 2
         b) 2 to 3
         c) 3 to 4
         d) 4 to 5
         e) 5 to 6

2.3) Which of the following is NOT a drug exhibiting zero-order elimination kinetics?
         a) Aspirin
         b) Morphine
         c) Phenytoin
         d) ETOH