PHARMACOKINETICS
TOP 10 MCQ
1. ______ is expressed in both the intestinal epithelium and the kidney [GPAT-2024]
(a) CYP2D6
(b) CYP1A2
(c) CYP3A4
(d) CYP2E1
2. Which of the following describes the effect of reversible drug binding to plasma proteins?
(a) It accelerates drug metabolism
(b) It promotes rapid elimination of the drug
(c) It sequesters drugs in a non-diffusible form
(d) It reduces drug accumulation in tissues
3. A 70 kg woman was administered 1000 mg of the drug as i.v. bolus. After its uniform distribution in the body, the plasma concentration of the drug was found to be 50 mg/L. What is its volume of distribution [GPAT-2023 SHIFT-I]
(a) 70 L
(b) 500 L
(c) 20 L
(d) 0.1 L
4. Which of the following could be the reason(s) for Pharmacokinetic Drug Interactions
[P] Interference with absorption
[Q] Changes in protein binding
[R] Competition at receptor sites
[S] Interference with renal excretion
Choose the correct answer from the options given below [GPAT-2022]
(a) P, Q and R only
(b) P, Q and S only
(c) P, T and D only
(d) R only
5. Ion trapping is an important process in drug distribution with potential therapeutic benefit. It is defined as [GPAT-2021]
(a) An acidic drug will accumulate on the more basic side of the membrane and a basic drug on more basic side
(b) An acidic drug will accumulate on the more acidic side of the membrane and a basic drug on more basic side
(c) An acidic drug will accumulate on the more basic side of the membrane and a basic drug on more acidic side
(d) An acidic drug will accumulate on the more acidic side of the membrane and a basic drug on more acidic side
6. Numerous isomers of human liver P450 enzyme have been identified, it is not worthy that alone is responsible for the metabolism of over 50% of the prescription drugs metabolized by liver [GPAT-2019]
(a) CYP3A4
(b) CYP2A6
(c) CYP1A1
(d) CYP2B6
7. Which of the following is a characteristic of cytochrome P-450 [GPAT-2017]
(a) Catalyzes aromatic and aliphatic hydroxylation
(b) Located in the lipophilic environment of mitochondrial membrane
(c) Catalyzes O-, S-, N-methylation reactions
(d) Catalyzes conjugation reactions
8. Identify the FALSE statements [GPAT-2016]
(a) A characteristic of drugs eliminated by zero order kinetic process is that the half-life is not constant
(b) The plasma drug concentration versus time curve for a drug eliminated by zero order kinetics is linear
(c) A fundamental characteristic of all first order pharmacokinetics processes is that the rate of the process is proportional to drug concentration
(d) A characteristic of absorption by lipid diffusion is its saturability at high drug concentrations
9. Therapeutic Index is [GPAT-2015]
(a) ED50 / LD50
(b) LD50 / ED50
(c) ED50 − LD50
(d) ED50 × LD50
10. What is the effect of increased clearance on the half-life of a drug
(a) Increases half-life
(b) Decreases half-life
(c) No effect on half-life
(d) Depends on bioavailability
ANSWER KEY
| 1-c | 2-c | 3-c | 4-b | 5-c | 6-a | 7-a | 8-a | 9-b | 10-b |
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