front 1 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 | back 1 B. Xenobiotics |
front 2 A drug’s biologic activity may be terminated or altered by which alternative process after absorption? A) Filtration B) Sequestration C) Metabolism D) Diffusion | back 2 C. Metabolism |
front 3 Lipophilic xenobiotics are generally transformed into products that are more: A) Volatile B) Polar C) Protein-bound D) Lipophilic | back 3 B. Polar |
front 4 Biotransformation of lipophilic xenobiotics usually improves their: A) Tissue storage B) Renal excretion C) Protein binding D) Membrane retention | back 4 B. Renal excretion |
front 5 Some biotransformation reactions can produce metabolites with what unexpected effect? A) Enhanced activity B) Reduced absorption C) Less polarity D) Impaired distribution | back 5 A. Enhanced activity |
front 6 Some drug biotransformations are clinically important because they can generate: A) Inert proteins B) Toxic products C) Bile salts D) Digestive enzymes | back 6 B. Toxic products |
front 7 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 | back 7 B. Renal elimination |
front 8 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 | back 8 A. Phase I |
front 9 Phase I reactions usually convert the parent drug into a metabolite that is more: A) Acidic B) Polar C) Reduced D) Lipophilic | back 9 B. Polar |
front 10 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 | back 10 B. Phase I reaction |
front 11 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 | back 11 B. Phase II |
front 12 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 | back 12 C. Polar conjugate |
front 13 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 | back 13 C. Before phase I |
front 14 The principal organ responsible for drug metabolism is the: A) Kidney B) Liver C) Spleen D) Lung | back 14 B. Liver |
front 15 The lower gut can metabolize drugs partly because it contains intestinal: A) Hepatocytes B) Microorganisms C) Kupffer cells D) Goblet cells | back 15 B. Microorganisms |
front 16 Besides lower-gut microorganisms, which gut factor can directly metabolize some drugs? A) Gastric acid B) Bile pigments C) Portal albumin D) Splenic enzymes | back 16 A. Gastric acid |
front 17 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 | back 17 B. Intestinal wall |
front 18 Many drug-metabolizing enzymes are located in which cellular structure? A) Nuclear pores B) Lipophilic ER membrane C) Lysosomal lumen D) Mitochondrial matrix | back 18 B. Lipophilic ER membrane |
front 19 The endoplasmic reticulum location of many drug-metabolizing enzymes is important because many substrates are: A) Hydrophilic B) Lipophilic C) Ionic D) Proteinaceous | back 19 B. Lipophilic |
front 20 After cell fractionation, which structures retain many morphologic and functional features of intact ER membranes? A) Ribosomes B) Microsomes C) Lysosomes D) Peroxisomes | back 20 B. Microsomes |
front 21 Smooth microsomes contain which important class of drug-metabolizing enzymes? A) Monooxygenases B) Hydrolases C) Kinases D) Transferases | back 21 A. Monooxygenases |
front 22 Microsomal monooxygenase activity requires NADPH as a reducing agent and molecular: A) Nitrogen B) Carbon dioxide C) Oxygen D) Hydrogen | back 22 C. Oxygen |
front 23 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 | back 23 D. P450 reductase and P450 |
front 24 Cytochrome P450 oxidations depend on electron transfer from which enzyme? A) NADPH P450 oxidoreductase B) Alcohol dehydrogenase C) Xanthine oxidase D) Thiopurine methyltransferase | back 24 A. NADPH P450 oxidoreductase |
front 25 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 | back 25 B. Carbon monoxide |
front 26 P450 enzymes are relatively sluggish catalysts, so their biotransformation reactions are generally: A) Rapid B) Irreversible C) Slow D) Nonenzymatic | back 26 C. Slow |
front 27 Compared with many phase II reactions, P450-catalyzed reactions are generally: A) Slower B) Faster C) Nonenzymatic D) Conjugative | back 27 A. Slower |
front 28 Which cytochrome P450 isoform metabolizes over half of liver-metabolized prescription drugs? A) CYP2D6 B) CYP2E1 C) CYP1A2 D) CYP3A4 | back 28 D. CYP3A4 |
front 29 Which external category can induce P450 enzyme expression? A) Environmental chemicals B) Plasma proteins C) Bile acids D) Renal solutes | back 29 A. Environmental chemicals |
front 30 Environmental chemicals and pollutants can alter drug metabolism mainly by inducing: A) Albumin synthesis B) P450 enzymes C) Renal filtration D) Bile secretion | back 30 B. P450 enzymes |
front 31 After ligand binding, PXR, CAR, and PPAR-alpha induce P450 genes by forming: A) Homodimers B) Heterodimers C) Monomers D) Tetramers | back 31 B. Heterodimers |
front 32 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 | back 32 A. P450 gene expression |
front 33 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 | back 33 B. Imidazole drugs |
front 34 Macrolide antibiotics can be metabolized into complexes that render cytochrome P450 catalytically: A) Induced B) Inactive C) Soluble D) Excreted | back 34 B. Inactive |
front 35 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 | back 35 B. Suicide inhibitors |
front 36 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 | back 36 A. Suicide inhibitor |
front 37 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 | back 37 B. P450 reactions |
front 38 At therapeutic doses, acetaminophen is mainly cleared through glucuronidation and: A) Oxidation B) Sulfation C) Reduction D) Hydrolysis | back 38 B. Sulfation |
front 39 When acetaminophen intake exceeds therapeutic doses, glucuronidation and sulfation pathways become: A) Induced B) Saturated C) Deleted D) Inactivated | back 39 B. Saturated |
front 40 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 | back 40 A. P450 metabolism |
front 41 After acetaminophen overdose, which treatment protects against fulminant hepatotoxicity and death? A) N-acetylcysteine B) Vitamin K C) Deferoxamine D) Fomepizole | back 41 A. N-acetylcysteine |
front 42 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 | back 42 C. Genetic polymorphism |
front 43 Genetic polymorphisms in phase I enzymes can alter which drug property? A) Protein synthesis B) Bile production C) Pharmacokinetics D) Gastric emptying | back 43 C. Pharmacokinetics |
front 44 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 | back 44 B. Drug response |
front 45 Patients with CYP2C9*3 have much lower tolerance for which drug? A) Digoxin B) Warfarin C) Nicotine D) Mephenytoin | back 45 B. Warfarin |
front 46 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 | back 46 C. Single nucleotide polymorphism |
front 47 The CYP2A6 gene is especially responsible for oxidation of which substance? A) Warfarin B) Digoxin C) Nicotine D) Mephenytoin | back 47 C. Nicotine |
front 48 Tobacco smokers with low CYP2A6 activity tend to consume: A) More tobacco B) Less tobacco C) Equal tobacco D) No tobacco | back 48 B. Less tobacco |
front 49 Low CYP2A6 activity in smokers is associated with a lower incidence of: A) Colon cancer B) Liver failure C) Lung cancer D) Renal cancer | back 49 C. Lung cancer |
front 50 Women, particularly Hispanic American women, express what hepatic CYP2B6 protein level compared with men? A) Lower B) Absent C) Equal D) Higher | back 50 D. Higher |
front 51 The slow acetylator phenotype occurs in about what percentage of Black and White Americans? A) 10% B) 25% C) 50% D) 90% | back 51 C. 50% |
front 52 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 | back 52 A. High northern latitudes |
front 53 The slow acetylator phenotype is inherited as which trait? A) X-linked dominant B) Autosomal recessive C) Autosomal dominant D) Mitochondrial | back 53 B. Autosomal recessive |
front 54 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 | back 54 A. Human gut microbiome |
front 55 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 | back 55 A. Two-fold |
front 56 Antibiotic-induced increases in serum digoxin raise the risk of which toxicity? A) Nephrotoxicity B) Cardiotoxicity C) Ototoxicity D) Hepatotoxicity | back 56 B. Cardiotoxicity |
front 57 Cigarette smokers metabolize some drugs faster than nonsmokers primarily because of: A) Renal filtration B) Enzyme induction C) Protein displacement D) Gastric emptying | back 57 B. Enzyme induction |
front 58 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 | back 58 C. Competitive inhibition |
front 59 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 | back 59 C. Higher doses |
front 60 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 | back 60 A. Enzyme induction |
front 61 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 | back 61 B. St. John’s wort |
front 62 St. John’s wort is commonly taken as an herbal treatment for: A) Hypertension B) Depression C) Constipation D) Insomnia | back 62 B. Depression |
front 63 An inducer may enhance metabolism of other drugs and also its: A) Own metabolism B) Renal secretion C) Protein binding D) Receptor affinity | back 63 A. Own metabolism |
front 64 Progressively reduced therapeutic effectiveness from enhanced metabolism of the same drug is called: A) Dependence B) Resistance C) Tolerance D) Withdrawal | back 64 C. Tolerance |
front 65 Which substance is a CYP3A4 substrate inhibitor? A) Rifampin B) Ketoconazole C) Phenobarbital D) Carbamazepine | back 65 B. Ketoconazole |
front 66 Which antibiotic is a CYP3A4 substrate inhibitor? A) Erythromycin B) Penicillin C) Cefazolin D) Vancomycin | back 66 A. Erythromycin |
front 67 Which dietary exposure can inhibit CYP3A4 substrates? A) Cranberry juice B) Grapefruit juice C) Orange juice D) Apple juice | back 67 B. Grapefruit juice |
front 68 Liver disease and pulmonary disease may affect which pharmacologic process? A) Drug metabolism B) Drug ingestion C) Drug formulation D) Drug packaging | back 68 A. Drug metabolism |
front 69 Viral infection, bacterial infection, cancer, and inflammation can impair drug metabolism by affecting: A) P450s B) Ribosomes C) Hemoglobin D) Aquaporins | back 69 A. P450s |
front 70 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 | back 70 B. Inactivating enzymes |
front 71 Inflammation can impair P450-mediated metabolism by inactivating P450s and enhancing their: A) Translation B) Degradation C) Conjugation D) Excretion | back 71 B. Degradation |
front 72 Pharmacologically active organic molecules tend to have which property at physiologic pH? A) Fully ionized B) Lipophilic C) Proteinaceous D) Highly polar | back 72 B. Lipophilic |
front 73 At physiologic pH, many pharmacologically active organic molecules remain unionized or: A) Fully oxidized B) Fully conjugated C) Partially ionized D) Irreversibly bound | back 73 C. Partially ionized |
front 74 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 | back 74 A. First-pass effect |
front 75 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 | back 75 C. Intestinal metabolism |
front 76 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 | back 76 B. Smooth microsomes |
front 77 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 | back 77 A. Water |
front 78 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 | back 78 D. P450 reductase and P450 |
front 79 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 | back 79 B. P450 reductase |
front 80 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 | back 80 C. P450 heme reduction |
front 81 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 | back 81 A. P450, reductase, NADPH, oxygen |
front 82 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 | back 82 C. Combines with drug substrate |
front 83 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 | back 83 D. Activated oxygen complex |
front 84 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 | back 84 B. High lipid solubility |
front 85 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 | back 85 B. P450 isoforms |
front 86 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 | back 86 A. Cytochrome P450 |
front 87 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 | back 87 B. Increased metabolism, decreased action If a drug induces its own P450 metabolism, it makes the liver better at breaking down that same drug over time. |
front 88 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 | back 88 A. Transcription, translation, heme synthesis |
front 89 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 | back 89 C. Prosthetic cofactor |
front 90 Cruciferous vegetables and omeprazole induce CYP1A through a cytoplasmic receptor for polycyclic aromatic hydrocarbons called: A) CAR B) PXR C) AhR D) RXR | back 90 C. AhR |
front 91 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 | back 91 A. Arnt |
front 92 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 | back 92 B. CYP1A |
front 93 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 | back 93 C. CYP3A |
front 94 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 | back 94 A. Lipid-lowering drugs |
front 95 A PPAR-alpha ligand induces P450 gene expression by forming a heterodimer with which nuclear receptor? A) AhR B) Arnt C) RXR D) PAPS | back 95 C. RXR |
front 96 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 | back 96 B) The enzyme gets broken down slower |
front 97 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 | back 97 A. Bind P450 heme iron |
front 98 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 | back 98 B. Suicide inhibitors |
front 99 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 | back 99 A. Drug conjugates |
front 100 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 | back 100 B. Cytosolic and microsomal GSH transferases |
front 101 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 | back 101 D. Aromatic amine or hydrazine |
front 102 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 | back 102 A. NAT1 and NAT2 |
front 103 N-acetyltransferases use which endogenous cofactor during acetylation reactions? A) NADPH B) PAPS C) Acetyl-CoA D) SAMe | back 103 C. Acetyl-CoA |
front 104 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 | back 104 A. O-, N-, and S-methylation |
front 105 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 | back 105 D. Epoxide hydrolases |
front 106 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 | back 106 A. P450-catalyzed oxidations |
front 107 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 | back 107 B. Nutrition and diet |
front 108 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 | back 108 A. P450-dependent GSH conjugation |
front 109 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 | back 109 C. Depleted faster than regenerated |
front 110 The toxic reactive metabolite that accumulates during acetaminophen overdose is best known as: A) Acetyl-CoA B) NAPQI C) PAPS D) SAMe | back 110 B. NAPQI |
front 111 NAPQI directly injures hepatocytes by reacting with nucleophilic groups on which target? A) Cellular proteins B) Plasma albumin C) Bile acids D) Ribosomal RNA | back 111 A. Cellular proteins |
front 112 Acetaminophen-induced hepatotoxicity involves direct hepatocellular damage and generation of: A) Nitric oxide B) Bile salts C) Reactive oxygen species D) Acetyl-CoA | back 112 C. Reactive oxygen species |
front 113 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 | back 113 D. Autosomal recessive |
front 114 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 | back 114 A. 3A4, 2C9, 2D6, 2C19, 1A2, 2B6 |
front 115 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 | back 115 B. Phase I drug metabolism |
front 116 Debrisoquin-sparteine oxidation polymorphism is inherited in which pattern? A) Autosomal recessive B) Autosomal dominant C) X-linked recessive D) Mitochondrial | back 116 A. Autosomal recessive |
front 117 Debrisoquin-sparteine oxidation polymorphism involves impaired oxidations dependent on which CYP enzyme? A) CYP3A4 B) CYP2C19 C) CYP2D6 D) CYP1A2 | back 117 C. CYP2D6 |
front 118 Which CYP2C19 allele variant is associated with increased CYP2C19 activity? A) CYP2C19*2 B) CYP2C19*3 C) CYP2C19*17 D) CYP2C19*5 | back 118 C. CYP2C19*17 |
front 119 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 | back 119 A. Increased bleeding risk |
front 120 CYP3A5 variation is due to a single nucleotide polymorphism in intron 3 that alters: A) Heme synthesis B) Splicing C) Sulfation D) Acetylation | back 120 B. Splicing |
front 121 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 | back 121 B. Flavin monooxygenase |
front 122 “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 | back 122 A. Ziegler’s enzyme |
front 123 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 | back 123 C. Butyrylcholinesterase |
front 124 Succinylcholine is clinically used primarily as which type of drug? A) Anticoagulant B) Muscle relaxant C) Antidepressant D) Antifungal | back 124 B. Muscle relaxant |
front 125 Patients with butyrylcholinesterase deficiency metabolize succinylcholine slowly and are especially susceptible to: A) Severe hepatotoxicity B) Respiratory paralysis C) Bladder cancer D) Peripheral neuritis | back 125 B. Respiratory paralysis |
front 126 Which phenotype is associated with higher isoniazid-induced peripheral neuritis risk? A) Ultrarapid metabolizer B) Fast acetylator C) Slow acetylator D) CYP3A5 expresser | back 126 C. Slow acetylator |
front 127 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 | back 127 A. Slow acetylator |
front 128 Lack of S-methylation of aromatic sulfhydryl compounds is caused by polymorphism of which gene? A) BCHE B) TPMT C) CYP1A D) NAT1 | back 128 B. TPMT |
front 129 TPMT gene polymorphism increases risk of fatal hematopoietic toxicity from which drug class? A) Thiopurines B) Macrolides C) Barbiturates D) Antipsychotics | back 129 A. Thiopurines |
front 130 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 | back 130 A. Biotransform drugs |
front 131 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 | back 131 A. Beta-glucuronidases |
front 132 Gut microbial beta-glucuronidases are best classified as which enzyme type? A) Oxidases B) Hydrolases C) Ligases D) Reductases | back 132 B. Hydrolases |
front 133 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 | back 133 A. Portal circulation |
front 134 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 | back 134 B. Enterohepatic recycling |
front 135 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 | back 135 A) More toxicity |
front 136 Charcoal-broiled foods and cruciferous vegetables induce which enzyme family? A) CYP3A B) CYP2D6 C) CYP1A D) CYP2C19 | back 136 C. CYP1A |
front 137 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 | back 137 A. CYP2C9 and CYP2C19 |
front 138 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 | back 138 A. Pharmacologic effects |
front 139 Furanocoumarins in grapefruit juice irreversibly inactivate which P450 isoform in intestinal mucosa? A) CYP1A2 B) CYP2D6 C) CYP3A4 D) CYP2C9 | back 139 C. CYP3A4 |
front 140 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 | back 140 A. First-pass effect |
front 141 Impairment of intestinal first-pass metabolism by grapefruit juice tends to increase oral drug: A) Ionization B) Bioavailability C) Protein synthesis D) Glucuronidation | back 141 B. Bioavailability |
front 142 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 | back 142 A. Drug metabolism |
front 143 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 | back 143 A. Heavy metal poisoning |
front 144 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 | back 144 A. Drug metabolism |
front 145 Inflammatory mediators, cytokines, and nitric oxide impair drug metabolism mainly by inactivating: A) P450s B) Albumin C) Hemoglobin D) Aquaporins | back 145 A. P450s |
front 146 Drug metabolism in humans usually results in a product | back 146 (A) Less lipid soluble than the original drug Most drug metabolism happens in the liver and is meant to make drugs easier to eliminate. The body usually converts lipid-soluble drugs into more water-soluble (polar) metabolites so they can be excreted in urine or bile. |
front 147 If therapy with multiple drugs causes induction of drug
| back 147 (A) Be associated with increased smooth endoplasmic reticulum |
front 148 Which of the following factors is likely to increase the
duration of action of a drug that is metabolized by CYP3A4
in the | back 148 (B) Chronic therapy with amiodarone Amiodarone is recognized as an inhibitor of |
front 149 Which of the following agents, when used in combination | back 149 (F) Ritonavir Ritonavir inhibits hepatic drug metabolism, and its use at low
|
front 150 Which of the following drugs may inhibit the hepatic microsomal P450
responsible for warfarin metabolism? | back 150 (A) Amiodarone Amiodarone is an important antiarrhythmic drug and has a
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front 151 Which of the following drugs, if used chronically, is most
| back 151 (B) Ethanol |
front 152 Which of the following drugs has higher first-pass metabolism in men
than in women? | back 152 (B) Ethanol |
front 153 Which of the following drugs is an established inhibitor of
| back 153 (H) Verapamil |