Deck 20: Pharmacokinetics and Drug Kinetics

Question 1

What Will be the approximate Tmax of a drug exhibiting Ka of 2 hr-1 and K of 0.2 hr-1 ?

A)1.2 hr
B)2.4 hr
C)4.8 hr
D)2.0 hr

Answer 1

1.2 hr

Question 2

A drug solution has half life of 21 days. Assuming that drug undergoes first order kinetics, how long will it take for the potency to drop to 90% of initial potency?

A)3.2 days
B)9.6 days
C)16 days
D)6.2 days

Answer 2

3.2 days

Question 3

A suspension shows zero-order kinetic with a rate constant 2mg/ml.month. The dose of suspension is 20mg/ml. The biological half life of the above dosage form is

A)5 months
B)1 month
C)3 months
D)2 months

Answer 3

5 months

Question 4

Drug showing zero order kinetic of elimination

A)Are more common than those showing first order kinetic
B)Show plot of drug concentration vs time (linear Plot)
C)Decrease in concentration exponentially with time
D)Have half life independent of dose

Question 5

Elimination after 4 half lives in first order kinetics is

A)84%
B)93%
C)80%
D)4%

Question 6

Which one is irrational statement for first order kinetics?

A)Half life is a function of concentration of reactants
B)Reaction rate is not a function of concentration of reactants
C)Both a & b
D)All of these

Question 7

T % (Half life time) of a drug can determine all of the following except

A)Closing interval
B)Therapeutic dose
C)Elimination time
D)Steady plasma concentration

Question 8

The area under serum concentration time curve of drug represents

A)The biological half life of the drug
B)Amount of drug biotransformed
C)The amount of drug absorbed
D)The amount of drug excreted in urine

Question 9

Under non compartment analysis the following formula is used for calculation

A)MRT = AUMC / AUC
B)AUMC = MRT / AUC
C)MRT = AUC / AUMC
D)AUC = AUMC / MRT

Question 10

Under compartment modeling, Wegner-Nelson-Method involves

A)Determination of absorption rate constant (Ka) from %ARA Vs time curve
B)Determination of elimination rate constant (Ka) from % ARA Vs time curve
C)Determination of absorption rate constant (Ke) from %ARA •Vs Concentration curve
D)Determination of plasma half life

Question 11

The steady-state concentration of a drug can be double by:

A)Doubling the both rate of infusion and concentration of drug.
B)Doubling the rate of infusion only.
C)Doubling the loading dose but maintaining the infusion rate.
D)Tripling the rate of infusion.

Question 12

In compartment modeling the term "Open" indicates

A)Unidirectional input and output
B)All compartments are open
C)Body is open
D)None of the above

Question 13

Select the formula to calculate steady state concentration follows IV infusion

A)Css= Infusion Rate/ Clearance
B)Css= Clearance / Infusion Rate
C)Css= Infusion Rate X Clearance
D)Css = Infusion Rate - Clearance

Question 14

IV infusion model follows

A)Zero order absorption and first order elimination kinetic
B)No absorption and first order elimination kinetic
C)No absorption and Zero order elimination kinetic
D)First order absorption and first order elimination kinetic

Question 15

Select the formula to calculate elimination half life

A)t1/2 = 0.693 + Ke
B)t1/2 = 0.693 / Ke
C)t1/2 = 0.693 × Ke
D)t1/2 = 0.693 - Ke

Question 16

The constants that represent reversible transfer of drug between compartments are called as

A)microconstants
B)macroconstant
C)Infusion
D)Lag time

Question 17

In two compartment model, extravascular route of drug administration, there are ……phases

A)absorption phase,
B)Distribution phase
C)elimination phase,
D)All of the above

Question 18

Ka is estimated by

A)Method of Residuals
B)Loo Riegelman method
C)Both a and b
D)None of the above

Question 19

The central compartment consist of

A)Highly perfused tissues
B)Slowly equilibrate tissues
C)Both a and b
D)Reproductive org

Question 20

What does "pharmacokinetics" includes?

A)Mechanisms of drug action
B)Localization of drug action
C)Interaction of substances
D)Excretion of substances

Question 21

Pharmacokinetics is:

A)The study of absorption, distribution, metabolism and excretion of drugs
B)The study of biological and therapeutic effects of drugs
C)The study of methods of new drug development
D)The study of mechanisms of drug action

Question 22

What does "pharmacokinetics" includes?

A)Drug biotransformation in the organism
B)Influence of drugs on metabolism processes
C)Influence of drugs on genes
D)Complications of drug therapy

Question 23

Parenteral administration:

A)Is too slow for emergency use
B)Cannot be used with unconsciousness patients
C)Generally results in a less accurate dosage than oral administration
D)Usually produces a more rapid response than oral administration

Question 24

The volume of distribution (Vd) relates:

A)The amount of a drug in the body to the concentration of a drug in plasma
B)An uncharged drug reaching the systemic circulation
C)Single to a daily dose of an administrated drug
D)An administrated dose to a body weight

Question 25

For the calculation of the volume of distribution (Vd) one must take into account:

A)Concentration of substance in urine
B)Therapeutical width of drug action
C)A daily dose of drug
D)Concentration of a substance in plasma