Pharm 4 Flashcards

Substances absorbed across the lungs or skin, or ingested in food, drink, therapeutic drugs, or recreational drugs, are called:

A) Autacoids

B) Xenobiotics

C) Eicosanoids

D) Cofactors

A drug’s biologic activity may be terminated or altered by which alternative process after absorption?

A) Filtration

B) Sequestration

C) Metabolism

D) Diffusion

Lipophilic xenobiotics are generally transformed into products that are more:

A) Volatile

B) Polar

C) Protein-bound

D) Lipophilic

Biotransformation of lipophilic xenobiotics usually improves their:

A) Tissue storage

B) Renal excretion

C) Protein binding

D) Membrane retention

Some biotransformation reactions can produce metabolites with what unexpected effect?

A) Enhanced activity

B) Reduced absorption

C) Less polarity

D) Impaired distribution

Some drug biotransformations are clinically important because they can generate:

A) Inert proteins

B) Toxic products

C) Bile salts

D) Digestive enzymes

Metabolic biotransformations usually occur between drug absorption into the circulation and which final process?

A) Hepatic uptake

B) Renal elimination

C) Gut secretion

D) Plasma binding

Which phase usually introduces or unmasks a functional group on the parent drug?

A) Phase I

B) Phase II

C) Phase III

D) Enterohepatic cycling

Phase I reactions usually convert the parent drug into a metabolite that is more:

A) Acidic

B) Polar

C) Reduced

D) Lipophilic

A drug undergoes oxidation that unmasks a hydroxyl group before conjugation. This first reaction is best classified as:

A) Phase II metabolism

B) Phase I reaction

C) Renal elimination

D) Microsomal storage

Which metabolic phase combines an endogenous substrate with a functional group to form a polar conjugate?

A) Phase I

B) Phase II

C) Phase III

D) Phase IV

The major functional result of many phase II reactions is formation of a highly:

A) Lipophilic conjugate

B) Volatile compound

C) Polar conjugate

D) Reactive radical

Although often taught as sequential, phase II reactions may sometimes occur when relative to phase I reactions?

A) Always after

B) Never independently

C) Before phase I

D) Only after excretion

The principal organ responsible for drug metabolism is the:

A) Kidney

B) Liver

C) Spleen

D) Lung

The lower gut can metabolize drugs partly because it contains intestinal:

A) Hepatocytes

B) Microorganisms

C) Kupffer cells

D) Goblet cells

Besides lower-gut microorganisms, which gut factor can directly metabolize some drugs?

A) Gastric acid

B) Bile pigments

C) Portal albumin

D) Splenic enzymes

Drug metabolism in the gut can also be mediated by digestive enzymes and enzymes in the:

A) Colonic lumen

B) Intestinal wall

C) Portal vein

D) Pancreatic duct

Many drug-metabolizing enzymes are located in which cellular structure?

A) Nuclear pores

B) Lipophilic ER membrane

C) Lysosomal lumen

D) Mitochondrial matrix

The endoplasmic reticulum location of many drug-metabolizing enzymes is important because many substrates are:

A) Hydrophilic

B) Lipophilic

C) Ionic

D) Proteinaceous

After cell fractionation, which structures retain many morphologic and functional features of intact ER membranes?

A) Ribosomes

B) Microsomes

C) Lysosomes

D) Peroxisomes

Smooth microsomes contain which important class of drug-metabolizing enzymes?

A) Monooxygenases

B) Hydrolases

C) Kinases

D) Transferases

Microsomal monooxygenase activity requires NADPH as a reducing agent and molecular:

A) Nitrogen

B) Carbon dioxide

C) Oxygen

D) Hydrogen

Which pair participates in microsomal oxidation-reduction drug metabolism?

A) NADH and catalase

B) Glutathione and transferase

C) Aldehyde and dehydrogenase

D) P450 reductase and P450

Cytochrome P450 oxidations depend on electron transfer from which enzyme?

A) NADPH P450 oxidoreductase

B) Alcohol dehydrogenase

C) Xanthine oxidase

D) Thiopurine methyltransferase

Which molecule binds reduced cytochrome P450 to produce its characteristic 450-nm absorbance?

A) Nitric oxide

B) Carbon monoxide

C) Molecular oxygen

D) Carbon dioxide

P450 enzymes are relatively sluggish catalysts, so their biotransformation reactions are generally:

A) Rapid

B) Irreversible

C) Slow

D) Nonenzymatic

Compared with many phase II reactions, P450-catalyzed reactions are generally:

A) Slower

B) Faster

C) Nonenzymatic

D) Conjugative

Which cytochrome P450 isoform metabolizes over half of liver-metabolized prescription drugs?

A) CYP2D6

B) CYP2E1

C) CYP1A2

D) CYP3A4

Which external category can induce P450 enzyme expression?

A) Environmental chemicals

B) Plasma proteins

C) Bile acids

D) Renal solutes

Environmental chemicals and pollutants can alter drug metabolism mainly by inducing:

A) Albumin synthesis

B) P450 enzymes

C) Renal filtration

D) Bile secretion

After ligand binding, PXR, CAR, and PPAR-alpha induce P450 genes by forming:

A) Homodimers

B) Heterodimers

C) Monomers

D) Tetramers

PXR, CAR, and PPAR-alpha are best described as ligand-regulated receptors that affect:

A) P450 gene expression

B) Ribosomal assembly

C) Lysosomal acidification

D) Albumin filtration

Which drug class binds tightly to P450 heme iron and competitively inhibits endogenous substrate metabolism?

A) Beta-lactams

B) Imidazole drugs

C) Loop diuretics

D) Bile resins

Macrolide antibiotics can be metabolized into complexes that render cytochrome P450 catalytically:

A) Induced

B) Inactive

C) Soluble

D) Excreted

Inactivators that attack the heme or protein portion of cytochrome P450 are called:

A) Competitive blockers

B) Suicide inhibitors

C) Allosteric activators

D) Phase II cofactors

A compound irreversibly damages the protein moiety of a P450 enzyme during metabolism. This compound is best classified as a:

A) Suicide inhibitor

B) Reducing agent

C) Response element

D) Polar conjugate

Phase II reactions usually accelerate drug biotransformation because they are generally faster than:

A) Gastric hydrolysis

B) P450 reactions

C) Renal filtration

D) Plasma diffusion

At therapeutic doses, acetaminophen is mainly cleared through glucuronidation and:

A) Oxidation

B) Sulfation

C) Reduction

D) Hydrolysis

When acetaminophen intake exceeds therapeutic doses, glucuronidation and sulfation pathways become:

A) Induced

B) Saturated

C) Deleted

D) Inactivated

Acetaminophen overdose becomes dangerous partly because saturation of conjugation pathways increases reliance on:

A) P450 metabolism

B) Bile acid transport

C) Albumin binding

D) Digestive enzymes

After acetaminophen overdose, which treatment protects against fulminant hepatotoxicity and death?

A) N-acetylcysteine

B) Vitamin K

C) Deferoxamine

D) Fomepizole

A population has a variant allele frequency above 1% that changes gene expression or function. This is called:

A) Epigenetic silencing

B) Drug tolerance

C) Genetic polymorphism

D) Enzyme induction

Genetic polymorphisms in phase I enzymes can alter which drug property?

A) Protein synthesis

B) Bile production

C) Pharmacokinetics

D) Gastric emptying

Polymorphisms in phase I metabolism can change pharmacokinetics and the magnitude or duration of:

A) Bile flow

B) Drug response

C) Albumin binding

D) Renal perfusion

Patients with CYP2C9*3 have much lower tolerance for which drug?

A) Digoxin

B) Warfarin

C) Nicotine

D) Mephenytoin

CYP3A5 polymorphism is known to result from what type of intron 3 change?

A) Frameshift deletion

B) Promoter methylation

C) Single nucleotide polymorphism

D) Trinucleotide expansion

The CYP2A6 gene is especially responsible for oxidation of which substance?

A) Warfarin

B) Digoxin

C) Nicotine

D) Mephenytoin

Tobacco smokers with low CYP2A6 activity tend to consume:

A) More tobacco

B) Less tobacco

C) Equal tobacco

D) No tobacco

Low CYP2A6 activity in smokers is associated with a lower incidence of:

A) Colon cancer

B) Liver failure

C) Lung cancer

D) Renal cancer

Women, particularly Hispanic American women, express what hepatic CYP2B6 protein level compared with men?

A) Lower

B) Absent

C) Equal

D) Higher

The slow acetylator phenotype occurs in about what percentage of Black and White Americans?

A) 10%

B) 25%

C) 50%

D) 90%

Slow acetylator phenotype is common in Europeans living in which region?

A) High northern latitudes

B) Equatorial coastal regions

C) Low southern latitudes

D) Tropical island regions

The slow acetylator phenotype is inherited as which trait?

A) X-linked dominant

B) Autosomal recessive

C) Autosomal dominant

D) Mitochondrial

Besides host genetics, what plays a significant role in drug responses?

A) Human gut microbiome

B) Pulmonary surfactant

C) Bone marrow reserve

D) Plasma sodium

Co-treatment of certain antibiotics with digoxin can raise serum digoxin by about:

A) Two-fold

B) Four-fold

C) Ten-fold

D) Twenty-fold

Antibiotic-induced increases in serum digoxin raise the risk of which toxicity?

A) Nephrotoxicity

B) Cardiotoxicity

C) Ototoxicity

D) Hepatotoxicity

Cigarette smokers metabolize some drugs faster than nonsmokers primarily because of:

A) Renal filtration

B) Enzyme induction

C) Protein displacement

D) Gastric emptying

Residual drug at an active site may inhibit metabolism of another simultaneous drug by what mechanism?

A) Allosteric activation

B) Irreversible binding

C) Competitive inhibition

D) Gene induction

Patients routinely ingesting certain antipsychotics or barbiturates may require what warfarin dose adjustment?

A) Lower doses

B) No doses

C) Higher doses

D) Alternate-day doses

A chronic barbiturate user starts warfarin and needs a higher dose. The best explanation is:

A) Enzyme induction

B) Phase II blockade

C) Renal failure

D) Gut sterilization

Which over-the-counter herbal medicine for depression causes many drug-drug interactions?

A) Kava

B) St. John’s wort

C) Valerian root

D) Ginkgo biloba

St. John’s wort is commonly taken as an herbal treatment for:

A) Hypertension

B) Depression

C) Constipation

D) Insomnia

An inducer may enhance metabolism of other drugs and also its:

A) Own metabolism

B) Renal secretion

C) Protein binding

D) Receptor affinity

Progressively reduced therapeutic effectiveness from enhanced metabolism of the same drug is called:

A) Dependence

B) Resistance

C) Tolerance

D) Withdrawal

Which substance is a CYP3A4 substrate inhibitor?

A) Rifampin

B) Ketoconazole

C) Phenobarbital

D) Carbamazepine

Which antibiotic is a CYP3A4 substrate inhibitor?

A) Erythromycin

B) Penicillin

C) Cefazolin

D) Vancomycin

Which dietary exposure can inhibit CYP3A4 substrates?

A) Cranberry juice

B) Grapefruit juice

C) Orange juice

D) Apple juice

Liver disease and pulmonary disease may affect which pharmacologic process?

A) Drug metabolism

B) Drug ingestion

C) Drug formulation

D) Drug packaging

Viral infection, bacterial infection, cancer, and inflammation can impair drug metabolism by affecting:

A) P450s

B) Ribosomes

C) Hemoglobin

D) Aquaporins

Inflammatory mediators, cytokines, and nitric oxide impair drug metabolism partly by doing what to P450s?

A) Activating transcription

B) Inactivating enzymes

C) Enhancing absorption

D) Increasing secretion

Inflammation can impair P450-mediated metabolism by inactivating P450s and enhancing their:

A) Translation

B) Degradation

C) Conjugation

D) Excretion

Pharmacologically active organic molecules tend to have which property at physiologic pH?

A) Fully ionized

B) Lipophilic

C) Proteinaceous

D) Highly polar

At physiologic pH, many pharmacologically active organic molecules remain unionized or:

A) Fully oxidized

B) Fully conjugated

C) Partially ionized

D) Irreversibly bound

After oral administration, many drugs are absorbed from the small intestine and carried through the portal system to the liver for extensive metabolism before systemic circulation. This is called:

A) First-pass effect

B) Renal clearance

C) Phase II conjugation

D) Enterohepatic recycling

Intestinal metabolism can contribute to first-pass elimination, and patients with impaired liver function may rely more on which site for drug elimination?

A) Renal tubules

B) Pulmonary alveoli

C) Intestinal metabolism

D) Splenic macrophages

Microsomes retain rough and smooth ER features. Which microsomes are relatively rich in enzymes responsible for oxidative drug metabolism?

A) Rough microsomes

B) Smooth microsomes

C) Ribosomal microsomes

D) Nuclear microsomes

In a typical microsomal monooxygenase reaction, one oxygen atom enters the drug product while the other oxygen atom becomes:

A) Water

B) Carbon monoxide

C) Carbon dioxide

D) Hydrogen peroxide

Which two microsomal enzymes are central to the mixed-function oxidase system

A) Catalase and peroxidase

B) Glucuronidase and sulfatase

C) Dehydrogenase and reductase

D) P450 reductase and P450

In the microsomal mixed-function oxidase system, NADPH donates electrons through which flavoprotein enzyme?

A) Cytochrome b5

B) P450 reductase

C) Alcohol dehydrogenase

D) Glutathione reductase

In the microsomal drug oxidation system, which step is rate-limiting for hepatic drug oxidations?

A) Drug binding to P450

B) Oxygen release from water

C) P450 heme reduction

D) Product diffusion away

Which set contains the four required components for microsomal drug oxidation?

A) P450, reductase, NADPH, oxygen

B) P450, glucuronide, ATP, oxygen

C) NADH, transferase, sulfate, oxygen

D) CYP3A4, albumin, ATP, water

In the first major step of microsomal drug oxidation, oxidized Fe3+ P450 does what?

A) Releases oxidized product

B) Forms water immediately

C) Combines with drug substrate

D) Conjugates with glucuronide

During microsomal drug oxidation, a second electron from NADPH via P450 reductase reduces oxygen, producing what intermediate?

A) Polar conjugate

B) Free drug radical

C) Inactive heme complex

D) Activated oxygen complex

The microsomal oxidase system can oxidize many unrelated substrates because substrate specificity is very low; the main shared substrate feature is:

A) High water solubility

B) High lipid solubility

C) Strong protein binding

D) Complete ionization

Which enzyme family catalyzes the bulk of hepatic drug and xenobiotic metabolism, including isoforms such as CYP1A2, CYP2C9, and CYP3A4?

A) UDP transferases

B) P450 isoforms

C) Sulfotransferases

D) Alcohol dehydrogenases

In drug metabolism terminology, the abbreviation CYP refers to which hepatic xenobiotic-metabolizing enzyme family?

A) Cytochrome P450

B) Cytosolic phosphatase

C) Conjugated pyridoxal

D) Carbamoyl phosphate

A drug repeatedly administered to a patient induces its own P450 metabolism. What is the expected effect on substrate metabolism and pharmacologic action?

A) Decreased metabolism, increased action

B) Increased metabolism, decreased action

C) Increased metabolism, increased action

D) Decreased metabolism, decreased action

For increased P450 synthesis during enzyme induction, what cellular processes must increase?

A) Transcription, translation, heme synthesis

B) Translation, excretion, bile secretion

C) Degradation, oxidation, conjugation

D) Filtration, secretion, reabsorption

In P450 induction, increased synthesis of heme is important because heme functions as the enzyme’s:

A) Competitive inhibitor

B) Endogenous substrate

C) Prosthetic cofactor

D) Nuclear receptor

Cruciferous vegetables and omeprazole induce CYP1A through a cytoplasmic receptor for polycyclic aromatic hydrocarbons called:

A) CAR

B) PXR

C) AhR

D) RXR

During CYP1A induction, the inducer-AhR complex translocates into the nucleus and dimerizes with which nuclear protein?

A) Arnt

B) RXR

C) PAPS

D) POR

After AhR-Arnt dimerization in CYP1A induction, the complex activates regulatory genes for which P450 isoform family?

A) CYP2B

B) CYP1A

C) CYP3A

D) CYP2C

Pregnane X receptor, a steroid-retinoid-thyroid receptor family member, mediates induction of which P450 isoform family?

A) CYP1A

B) CYP2A6

C) CYP3A

D) CYP2D6

PPAR-alpha is highly expressed in the liver and kidneys and uses which type of drugs as ligands?

A) Lipid-lowering drugs

B) Beta-lactam antibiotics

C) Opioid analgesics

D) H2 blockers

A PPAR-alpha ligand induces P450 gene expression by forming a heterodimer with which nuclear receptor?

A) AhR

B) Arnt

C) RXR

D) PAPS

P450 enzymes can be increased when a drug/substrate makes the enzyme more stable. What does this mean?

A) The enzyme gets broken down faster
B) The enzyme gets broken down slower
C) The enzyme is blocked by competition
D) The enzyme is permanently destroyed

How do imidazole-containing drugs inhibit P450-mediated metabolism of endogenous substrates and drugs?

A) Bind P450 heme iron

B) Deplete sulfate donors

C) Destroy UGT genes

D) Activate CAR receptors

Substrates that irreversibly inhibit P450s through reactive intermediates attacking apoprotein or heme moieties are called:

A) Substrate stabilizers

B) Suicide inhibitors

C) Nuclear ligands

D) Polar conjugates

Phase I metabolites often undergo conjugation with endogenous substances to form polar, readily excreted, usually inactive products called:

A) Drug conjugates

B) Free radicals

C) Active intermediates

D) Lipid stores

Which glutathione transferases are involved in metabolism of drugs/xenobiotics and leukotrienes/prostaglandins, respectively?

A) NAT1 and NAT2

B) Cytosolic and microsomal GSH transferases

C) UGT and SULT enzymes

D) Methyltransferase and epoxide hydrolase

N-acetyltransferases most directly catalyze metabolism of substrates containing which chemical moiety?

A) Sulfate ester or hydrazine

B) Epoxide ring or hydrazine

C) Steroid nucleus or hydrazine

D) Aromatic amine or hydrazine

N-acetyltransferases are encoded primarily by which two genes?

A) NAT1 and NAT2

B) CYP1A2 and CYP3A4

C) UGT1 and UGT2

D) SULT1 and SULT2

N-acetyltransferases use which endogenous cofactor during acetylation reactions?

A) NADPH

B) PAPS

C) Acetyl-CoA

D) SAMe

SAMe-mediated xenobiotic metabolism can include which methylation reactions?

A) O-, N-, and S-methylation

B) N-, P-, and C-methylation

C) O-, C-, and P-methylation

D) S-, P-, and C-methylation

A P450-catalyzed oxidation generates a reactive epoxide from a xenobiotic. Which enzyme class hydrolyzes this epoxide?

A) Sulfotransferases

B) Glutathione transferases

C) N-acetyltransferases

D) Epoxide hydrolases

Epoxide hydrolases are important because they hydrolyze epoxides generated by which process?

A) P450-catalyzed oxidations

B) UGT-mediated conjugations

C) NAT-mediated acetylations

D) SAMe-mediated methylations

Which factor plays a critical role in regulation of drug conjugation reactions?

A) Pulmonary pressure

B) Nutrition and diet

C) Gastric motility

D) Splenic filtration

Acetaminophen is normally metabolized by glucuronidation, sulfation, and which third pathway?

A) P450-dependent GSH conjugation

B) NAT-dependent acetylation

C) SAMe-dependent methylation

D) Epoxide hydrolase cleavage

In acetaminophen overdose, hepatic injury begins because hepatic GSH is:

A) Overproduced rapidly

B) Converted to sulfate

C) Depleted faster than regenerated

D) Secreted into bile

The toxic reactive metabolite that accumulates during acetaminophen overdose is best known as:

A) Acetyl-CoA

B) NAPQI

C) PAPS

D) SAMe

NAPQI directly injures hepatocytes by reacting with nucleophilic groups on which target?

A) Cellular proteins

B) Plasma albumin

C) Bile acids

D) Ribosomal RNA

Acetaminophen-induced hepatotoxicity involves direct hepatocellular damage and generation of:

A) Nitric oxide

B) Bile salts

C) Reactive oxygen species

D) Acetyl-CoA

Defects in phase I oxidative metabolism are commonly inherited as which type of trait?

A) X-linked dominant

B) Autosomal dominant

C) Mitochondrial

D) Autosomal recessive

Which group of six liver CYPs accounts for about 75% of clinically relevant drug metabolism?

A) 3A4, 2C9, 2D6, 2C19, 1A2, 2B6

B) 2A6, 2E1, 4A, 1B1, 2J2, 3A5

C) 1A1, 2F1, 2S1, 3A7, 4F2, 11A1

D) 2R1, 2U1, 4B1, 8B1, 17A1, 21A2

Polymorphisms in CYP3A4, CYP2C9, CYP2D6, CYP2C19, CYP1A2, and CYP2B6 significantly influence which process?

A) Phase II conjugation

B) Phase I drug metabolism

C) Renal tubular secretion

D) Gastric drug absorption

Debrisoquin-sparteine oxidation polymorphism is inherited in which pattern?

A) Autosomal recessive

B) Autosomal dominant

C) X-linked recessive

D) Mitochondrial

Debrisoquin-sparteine oxidation polymorphism involves impaired oxidations dependent on which CYP enzyme?

A) CYP3A4

B) CYP2C19

C) CYP2D6

D) CYP1A2

Which CYP2C19 allele variant is associated with increased CYP2C19 activity?

A) CYP2C19*2

B) CYP2C19*3

C) CYP2C19*17

D) CYP2C19*5

CYP2C19*17 is associated with higher prodrug activation and which clinical risk?

A) Increased bleeding risk

B) Severe nicotine dependence

C) Lower acetaminophen toxicity

D) Reduced P450 transcription

CYP3A5 variation is due to a single nucleotide polymorphism in intron 3 that alters:

A) Heme synthesis

B) Splicing

C) Sulfation

D) Acetylation

Trimethylamine oxidation polymorphism causes “fish odor syndrome” in slow metabolizers because trimethylamine is largely metabolized by which enzyme?

A) Butyrylcholinesterase

B) Flavin monooxygenase

C) Thiopurine methyltransferase

D) Beta-glucuronidase

“Fish odor syndrome” suggests genetic variants can affect oxidative drug metabolism through non-P450 enzymes such as:

A) Ziegler’s enzyme

B) CYP3A4

C) CYP1A2

D) NAT2

A patient has prolonged paralysis after succinylcholine. Genetic deficiency of which enzyme most likely explains slower succinylcholine metabolism?

A) CYP3A4

B) NAT2

C) Butyrylcholinesterase

D) Beta-glucuronidase

Succinylcholine is clinically used primarily as which type of drug?

A) Anticoagulant

B) Muscle relaxant

C) Antidepressant

D) Antifungal

Patients with butyrylcholinesterase deficiency metabolize succinylcholine slowly and are especially susceptible to:

A) Severe hepatotoxicity

B) Respiratory paralysis

C) Bladder cancer

D) Peripheral neuritis

Which phenotype is associated with higher isoniazid-induced peripheral neuritis risk?

A) Ultrarapid metabolizer

B) Fast acetylator

C) Slow acetylator

D) CYP3A5 expresser

A patient takes isoniazid and gets nerve problems, like tingling or numbness, plus autoimmune-like side effects. Which type of drug-metabolism patient is this most likely?

A) Slow acetylator
B) CYP3A4 inducer
C) TPMT overexpresser
D) Fast flavin monooxygenase metabolizer

Lack of S-methylation of aromatic sulfhydryl compounds is caused by polymorphism of which gene?

A) BCHE

B) TPMT

C) CYP1A

D) NAT1

TPMT gene polymorphism increases risk of fatal hematopoietic toxicity from which drug class?

A) Thiopurines

B) Macrolides

C) Barbiturates

D) Antipsychotics

The human gut microbiome can significantly influence drug response because gut microflora can:

A) Biotransform drugs

B) Synthesize heme

C) Destroy P450 genes

D) Block filtration

Drugs glucuronidated in the liver may enter bile and reach the gut, where microbial enzymes remove glucuronide groups. Which enzymes do this?

A) Beta-glucuronidases

B) Flavin monooxygenases

C) N-acetyltransferases

D) Butyrylcholinesterases

Gut microbial beta-glucuronidases are best classified as which enzyme type?

A) Oxidases

B) Hydrolases

C) Ligases

D) Reductases

After gut de-glucuronidation, the pharmacologically active parent aglycone may be reabsorbed into which circulation?

A) Portal circulation

B) Pulmonary circulation

C) Coronary circulation

D) Lymphatic circulation

Reabsorption of active aglycone after gut de-glucuronidation can extend drug action through:

A) Renal filtration

B) Enterohepatic recycling

C) Pulmonary diffusion

D) Splenic sequestration

If a drug keeps getting recycled between the liver, bile, intestine, and back into the blood, the body is exposed to the drug for longer. If that drug is already close to the toxic range, what can happen?

A) More toxicity
B) Less absorption
C) Faster drug removal
D) Loss of an enzyme

Charcoal-broiled foods and cruciferous vegetables induce which enzyme family?

A) CYP3A

B) CYP2D6

C) CYP1A

D) CYP2C19

St. John’s wort is used for depression and induces CYP3A4, with lesser induction of which enzymes?

A) CYP2C9 and CYP2C19

B) CYP1A2 and CYP2D6

C) CYP2A6 and CYP2E1

D) CYP3A5 and CYP2B6

Simultaneous administration of two or more drugs can impair elimination of the more slowly metabolized drug and prolong its:

A) Pharmacologic effects

B) Gastric absorption

C) Protein synthesis

D) Renal uptake

Furanocoumarins in grapefruit juice irreversibly inactivate which P450 isoform in intestinal mucosa?

A) CYP1A2

B) CYP2D6

C) CYP3A4

D) CYP2C9

Grapefruit furanocoumarins enhance proteolytic degradation of intestinal CYP3A4, thereby impairing which process?

A) First-pass effect

B) Renal clearance

C) Biliary secretion

D) Gastric motility

Impairment of intestinal first-pass metabolism by grapefruit juice tends to increase oral drug:

A) Ionization

B) Bioavailability

C) Protein synthesis

D) Glucuronidation

Cardiac disease can alter drug metabolism primarily by affecting physiologic delivery and function of metabolizing organs, so it belongs among diseases that affect:

A) Drug metabolism

B) Drug formulation

C) Drug naming

D) Drug packaging

Which exposure is listed among common disease-related causes of altered drug metabolism?

A) Heavy metal poisoning

B) Lactose intolerance

C) Seasonal allergy

D) Iron deficiency

Endocrine dysfunction can alter drug handling because it is one of the conditions that affects:

A) Drug metabolism

B) Drug taste

C) Capsule dissolution

D) Tablet coating

Inflammatory mediators, cytokines, and nitric oxide impair drug metabolism mainly by inactivating:

A) P450s

B) Albumin

C) Hemoglobin

D) Aquaporins

Drug metabolism in humans usually results in a product
that is
(A) Less lipid soluble than the original drug
(B) More likely to distribute intracellularly
(C) More likely to be reabsorbed by kidney tubules
(D) More lipid soluble than the original drug
(E) Less water soluble than the original drug

If therapy with multiple drugs causes induction of drug
metabolism in your depressed patient, it will
(A) Be associated with increased smooth endoplasmic reticulum
(B) Be associated with increased rough endoplasmic reticulum
(C) Be associated with decreased enzymes in the soluble
cytoplasmic fraction
(D) Require 3–4 months to reach completion

Which of the following factors is likely to increase the duration of action of a drug that is metabolized by CYP3A4 in the
liver?
(A) Chronic administration of rifampin during therapy with
the drug in question
(B) Chronic therapy with amiodarone
(C) Displacement from tissue-binding sites by another drug
(D) Increased cardiac output
(E) Chronic administration of carbamazepin

Which of the following agents, when used in combination
with other anti-HIV drugs, permits dose reductions?
(E) Quinidine
(F) Ritonavir
(G) Succinylcholine
(H) Verapamil

Which of the following drugs may inhibit the hepatic microsomal P450 responsible for warfarin metabolism?
(A) Amiodarone
(B) Ethanol
(C) Phenobarbital
(D) Procainamide
(E) Rifampin

Which of the following drugs, if used chronically, is most
likely to increase the toxicity of acetaminophen?
(A) Cimetidine
(B) Ethanol
(C) Ketoconazole
(D) Procainamide

Which of the following drugs has higher first-pass metabolism in men than in women?
(A) Cimetidine
(B) Ethanol
(C) Ketoconazole
(D) Procainamide

Which of the following drugs is an established inhibitor of
P-glycoprotein (P-gp) drug transporters?
(E) Quinidine
(F) Ritonavir
(G) Succinylcholine
(H) Verapamil