Drug Metabolism: A Comprehensive Guide for Pharmacy Students

Question 1

Which of the following reactions is NOT associated with Phase I drug metabolism?

Accepted Answer

Glucuronidation

Answer

Oxidation

Answer

Hydrolysis

Answer

Reduction

Question 2

Which of the following is the primary enzyme system involved in Phase I drug metabolism?

Accepted Answer

Cytochrome P450 enzymes

Answer

UDP-glucuronosyltransferases

Answer

Sulfotransferases

Answer

Esterases

Question 3

Glucuronidation, a Phase II metabolism reaction, involves the conjugation of a drug molecule with which substance?

Accepted Answer

Glucuronic acid

Answer

Acetyl coenzyme A

Answer

Glycine

Answer

Sulfate

Question 4

Which of the following is a potential consequence of increased drug metabolism?

Accepted Answer

Reduced drug efficacy

Answer

Increased drug toxicity

Answer

Enhanced drug absorption

Answer

Impaired drug distribution

Question 5

The liver is the primary organ responsible for drug metabolism. True or False?

Accepted Answer

True

Answer

False

Question 6

Which enzyme is involved in the cleavage of amide bonds in drugs?

Accepted Answer

Amidases

Answer

Cytochrome P450 enzymes

Answer

UDP-glucuronosyltransferases

Answer

Sulfotransferases

Question 7

Phase II metabolism reactions typically lead to:

Accepted Answer

Increased drug polarity

Answer

Increased drug activity

Answer

Decreased drug elimination

Answer

Reduced drug toxicity

Question 8

Drug interactions involving alterations in the activity of drug-metabolizing enzymes can have significant clinical implications. True or False?

Accepted Answer

True

Answer

False

Question 9

The enzyme primarily responsible for catalyzing Phase II glucuronidation reactions is:

Accepted Answer

UDP-glucuronosyltransferase

Answer

Cytochrome P450

Answer

Sulfotransferase

Answer

Acetyltransferase

Question 10

Which cytochrome P450 enzyme is involved in the metabolism of drugs such as warfarin, paracetamol, and erythromycin?

Accepted Answer

CYP3A4

Answer

CYP2D6

Answer

CYP1A2

Answer

CYP2C9

Question 11

Which of the following is **not** a suitable substrate for Phase II conjugation reactions?

Accepted Answer

Metals

Answer

Phenols

Answer

Carboxylic acids

Answer

Amines

Question 12

Identify the reaction that does NOT belong to Phase I metabolism:

Accepted Answer

Glucuronidation

Answer

Oxidation

Answer

Reduction

Answer

Hydrolysis

Question 13

Glucuronidation falls under which category of Phase II reactions?

Accepted Answer

Conjugation

Answer

Hydrolysis

Answer

Oxidation

Answer

Reduction

Question 14

Phenobarbital is known to:

Accepted Answer

Induce cytochrome P450 enzymes

Answer

Inhibit cytochrome P450 enzymes

Answer

Enhance drug absorption

Answer

Reduce drug toxicity

Question 15

CYP2D6 belongs to which class of enzymes?

Accepted Answer

Phase I oxidizing enzymes

Answer

Phase II conjugating enzymes

Answer

Transporter proteins

Answer

Receptors

Question 16

Drug metabolism primarily occurs in which organ?

Accepted Answer

Liver

Answer

Kidney

Answer

Lungs

Answer

Brain

Question 17

Genetic polymorphisms can influence drug metabolism. How do these variations impact a patient's response to medication?

Accepted Answer

Genetic polymorphisms can alter drug-metabolizing enzymes, affecting drug clearance and half-life.

Answer

Genetic polymorphisms have no significant impact on drug metabolism.

Answer

Genetic polymorphisms only affect Phase I drug metabolism reactions.

Answer

The impact of genetic polymorphisms on drug metabolism is always predictable for each patient.

Question 18

Which enzyme superfamily is primarily responsible for Phase I oxidative drug metabolism?

Accepted Answer

Cytochrome P450

Answer

Alcohol dehydrogenase

Answer

Glutathione S-transferase

Answer

Acetylcholinesterase

Question 19

Which of the following is a Phase II drug metabolism reaction?

Accepted Answer

Glucuronidation

Answer

Reduction

Answer

Oxidation

Answer

Hydrolysis

Question 20

The enzyme responsible for the majority of drug oxidation reactions is:

Accepted Answer

Cytochrome P450

Answer

Monoamine oxidase

Answer

Acetylcholinesterase

Answer

Alcohol dehydrogenase

Question 21

The primary purpose of Phase II reactions in drug metabolism is to:

Accepted Answer

Increase water solubility for elimination

Answer

Detoxify reactive metabolites

Answer

Activate prodrugs

Answer

Generate energy

Question 22

Which of the following is a common Phase II conjugation reaction?

Accepted Answer

Glucuronidation

Answer

Oxidation

Answer

Reduction

Answer

Hydrolysis

Question 23

The cytochrome P450 enzyme system is primarily located in which organ?

Accepted Answer

Liver

Answer

Brain

Answer

Kidney

Answer

Heart

Question 24

The study of drug metabolism, distribution, and excretion is known as:

Accepted Answer

Pharmacokinetics

Answer

Toxicology

Answer

Pharmacodynamics

Answer

Pharmacognosy