Drug Distribution MCQs with Answers

Biopharmaceutics & Pharmacokinetics (BP604TT)

Chapter 2 :- DRUG DISTRIBUTION

l. For the calculation of the volume of distribution (vd) one must take into account:
a. Concentration of a substance in plasma
b. A daily dose of drug
c. Concentration of substance in urine
d. Therapeutical width of drug action
Answer: a

2. Which process involve alteration of drug distribution
a. Competitive binding
b. Reduced plasma protein level
c: Both
d. None
Answer: c

3. If drug have very small volume of distribution it is likely that the drug
a. Has short biological half life
b. Does not accumulate in various tissue and organ
c. Not bioavailable
d. will not be effective
Answer: b

4. If distribution of drug is slower than process of biotransformation and elimination
a. It will cause high blood level of drug
b. It will cause low blood level of drug
c. Cause failure to attain diffusion equilibrium
d. None of the above
Answer: c

5. If the drug Y bind with plasma albumin with 10 times more affinity than drug X. Which the given statement is true?
a. Apparent volume of distribution of drug X decrease
b. Free concentration of drug X in blood will be increase
c. Apparent volume of distribution of drug Y decrease
d. Toxicity of drug Y increase
Answer: b

6. The distribution of drugs into the central nervous system (brain) usually depends on:
a. Aqueous diffusion
b. Lipid diffusion
c. Active transport
d. Facilitated transport
Answer: b

7. Which of the following is most likely to be associated with a high apparent volume of distribution
a. High hepatic extraction ratio
b. Penetration across the blood:brain and blood:testes barriers
c. Extensive binding to plasma protein
d. Extensive binding to tissue constituents
Answer: d

8. The Initial distribution of drug into the tissue is determined chiefly by
a. Rate of blood flow to tissue
b. Plasma protein binding of drug
c. Affinity for tissue
d. Gastric emptying time
Answer: a

9. Transfer of drug from plasma to tissue depends on
a. Weight of tissue
b. Blood perfusion rate of tissue
c. Size of tissue
d. All of the above
Answer: b

10. A hydrophilic medicinal agent has
a. Low ability to penetrate through the cell membrane lipids
b. Easy permeation through the blood-brain barrier
c. Penetrate through membranes by means of endocytosis
d. High reabsorption in renal tubules
Answer: a

11. Biological barriers include all except:
a. Renal tubules
b. Cell membranes
c. Capillary walls
d. Placenta
Answer: a

12. Blood Brain Barrier is maximum permeable to
a. Na+
b. C02
c. Cl-
d. K+
Answer: b

13. If a CNS drug is extensively ionized at pH of blood it will
a. Penetrate the blood brain barrier slowly
b. Penetrate the blood brain barrier rapidly
c. Not penetrate blood brain barrier
d. Be eliminated slowly
Answer: a

14. The rate of drug transport across a cell membrane by lipid diffusion depends on all of the following except
a. Drug size (diffusion constant)
b. Surface area of absorption
c. Lipid partition coefficient
d. Density of transporters

Answer: d

15. The formula to calculate half life (t1/2) is
a. 0.693 *Vd / C1
b. 0.693 *Cl / Vd
c. 0.693 / Cl * Vd
d. 0.693 / Cl
Answer: a

16. The procedure of transporting a drug from the bloodstream to tissues is called as
a) Absorption
b) Dissolution
c) Distribution
d) Elimination
Answer: c

17. …………..it represents the degree to which a drug is distributed in body tissue rather than
a) Volume of distribution (YD)
b) Effect of distribution
c) Area of distribution
d) None of the above
Answer: a

18. It is defined as the distribution of a drug between plasma and the rest of the body after oral or parenteral dosing.
a) Volume of distribution (VD)
b) Apparent volume of drug distribution
c) Phagocytosis
d) None of the above
Answer: b

19. The drugs having molecular size …………..easily cross capillary membrane.
a) <500-600d
b) < 100-200 d

c) <300-600d
d) <90M600d
Answer: a

20. The concentration of drug in blood or plasma will be comparatively in the GI tract.

1. a) High
2. b) Low
3. c) Very High
4. d) Very Low

Answer: b

21. Fat is act as reservoir for……………………… Drugs
a) Highly water soluble
b) Lower lipid soluble
c) Highly lipid soluble
d) Lower lipid soluble
Answer: c

22. Displacement is significant when, the displaced drug is more than protein bound.
a) 50%
b) 95%
c) 10%
d) 1%
Answer: b

23. ……………is located at the sertoli-sertoli cell junction.
a) Blood testis barrier
b) Blood CSF barrier
c) Blood cellular barrier
d) All of the above
Answer: a

24. The Binding Order of drug to tissue is…………………
a) Kidney > Liver > Lungs > Muscle
b) Muscle > Kidney > Lungs > Liver
c) Liver > Kidney > Lungs > Muscle

d) Liver > Lungs > Kidney > Muscle
Answer: c

25. …………………in lipophilicity increases the extend of binding.
a) Increase
b) Decrease
c) Constant
d) None of the above
Answer: a

26. Protein binding of drugs helps to maintain ……………for absorption of drugs.

1. (a) non sink condition
2. (b) sink condition
3. (c) pKa
4. (d) none of the above

Answer: b

27. The loading dose of a drug is based upon the
(a) time taken for complete elimination
(b) percentage of drug excreted unchanged in urine
(c) percentage of drug bound to plasma protein
(d) apparent volume of distribution and the desired drug concentration in plasma
Answer: d

28. The volume of distribution of drugs is:
(a) An expression of total body volume
(b) A measure of total fluid volume
(c) A relationship between the total amount of drug in the body and the concentration of the drug in the blood
(d) Proportional to bioavailability of the drug
Answer: c

29. What is the reason of complicated penetration of some drugs through brain-blood barrier?
(b) Meningitis
(c) Absence of pores in the brain capillary endothelium
(d) High endocytosis degree in a brain capillarc

(a) High lipid solubility of a drug
Answer: c

30. The volume of distribution (Vd) relates:
(a) Single to a daily dose of an administered drug
(b) An administered dose to a body weight
(c) An unchanged drug reaching the systemic circulation
(d) The amount of a drug in the body to the concentration of a drug in plasma
Answer: d

31. Movement of drug across the membrane is called as

1. (a) Symport
2. (b) Antiport
3. (c) Drug transport
4. (d) Absorption

Answer: c

32. Which of the following is known as Tamoxifen binding site?

1. (a) Site I
2. (b) Site II
3. (c) Site III
4. (d) Site IV

Answer: d

33. Which of the following drug selectively bound to extravascular tissues?

1. (a) Warfarin
2. (b) Diazepam
3. (c) Digitoxin
4. (d) Chloroquin

Answer: d

34. Plasma Protein binding …………..the volume of distribution of drugs.

1. (a) increases
2. (b) decreases
3. (c) no change
4. (d) none of the above

Answer: b

35. Following intravenous administration, drugs are distributed fastest to:

1. (a) the skin, kidney, and brain
2. (b) the liver, kidney, and brain
3. (c) the liver, adipose, and brain
4. (d) the liver, kidney, and adipose

Answer: b

36. …………is the tight junction between sertoli cells.

1. (a) BBB
2. (b) placental barrier
3. (c) blood-testis barrier
4. (d) endothelial barrier

Answer: c

37. Distribution is……………..
(a) irreversible process
(b) dynamic equilibrium process
(c) Both (a) & (b)
(d) none of the above
Answer: b

38. A drug reverses plasma-protein binding is often referred as……..

1. (a) displacer
2. (b) solvate
3. (c) carrier substance
4. (d) protein hydrolysate

Answer: a

39. Primary binding site for albumin is ………………binding site.

1. (a) Warfarin
2. (b) Diazepam
3. (c) Digitoxin
4. (d) Tamoxifen

Answer: a

40. Which of the following strategies are widely used to improve or promote transport of drug to brain?
(a) Glycosylation
(b) Use of Mannitol
(c) Prodrug approach
(d) All of the above
Answer: d

41. Acidic drug have
(a) Low Vd
(b) high Vd
(c) No Vd
(d) none of the above
Answer: a

42. Low molecular weight of drugs have
(a) Low Vd
(b) high Vd
(C) No Vd
(d) none of the above
Answer: b

43. Water soluble drugs have
(a) Low Vd
(b) high Vd
(c) No Vd
(d) none of the above
Answer: a

44. Lipid soluble drugs have
(a) Low Vd
(b) high Vd
(c) No Vd
(d) none of the above
Answer: b

45. Protein binding ……………the distribution of drugs.

1. (a) Decreases
2. (b) Increases
3. (c) No Change
4. (d) none of the above

Answer: a

46. Which one of the following physicochemical property is more important for passive diffusion of drugs from the GIT?
(a) Partition coefficient
(b) Lipid solubility
(c) pH of GIT fluids
(d) dissolution constana

Answer: a

47. Drug permeation through BBB can be improved by………..

1. (a) Glycosylation
2. (b) Mannitol
3. (c) Dihydropyridine redox system
4. (d) all of the above

Answer: d

48. Which of the following drug diffuses readily into the brain?

1. (a) Penicillin
2. (b) Thiopental
3. (c) Dopamine
4. (d) all of the above

Answer: b

49. Drug distribution in an organ depends on…………

1. (a) Organ size
2. (b) Perfusion rate
3. (c) Partition Coefficient
4. (d) all of the above

Answer: d

50. Protein binding of acidic drugs decreased in………..

1. (a) Trauma
2. (b) Surgery
3. (c) Hepatic Cirrhosis
4. (d) Burns Answers

Answer: d