Pharmacology - An Illustrated Review

Questions & Answers

Review Questions

1. Renal toxicity is associated with which of the following?

A.   Doxorubicin

B.   Fluorouracil

C.   Vincristine

D.   Cisplatin

E.   6-mercaptopurine

2. The antineoplastic action of which drug is related to its high affinity for dihydrofolate reductase?

A.   Fluorouracil

B.   Methotrexate

C.   Mechlorethamine

D.   Dactinomycin

E.   Vincristine

3. A 62-year-old African American man undergoes a hemicolectomy to remove an invasive adenocarcinoma from his ascending colon. Pathology shows pericolic lymph node involvement but no liver metastases. Based on the stage of the tumor, a course of treatment with leucovorin calcium, fluorouracil, and irinotecan hydrochloride is undertaken. What is the purpose of including leucovorin calcium?

A.   to provide normal cells with an active form of folic acid

B.   to decrease nausea and vomiting produced by fluorouracil

C.   to activate irinotecan

D.   to increase the effectiveness of fluorouracil

E.   to increase the uptake of drug into bone to prevent metastases

4. Cardiac toxicity is associated with which of the following?

A.   Doxorubicin

B.   Fluorouracil

C.   Vincristine

D.   Cisplatin

E.   6-mercaptopurine

5. Which one of the following drugs acts by inhibiting DNA topoisomerase?

A.   Cyclophosphamide

B.   Methotrexate

C.   Etoposide

D.   Leuprolide

E.   Fluorouracil

6. A 58-year-old woman noticed a lump in her right breast ~1 month ago. She has no pain, nipple discharge, itching, or swelling of the breast. The patient is postmenopausal and had a mammogram 2 years ago. She takes several supplements, including calcium/vitamin D and vitamin C. She also takes iron tablets for occasional mild anemia. Breast examination reveals a hard 1 cm mass in the upper right quadrant of her breast. Right axillary lymph nodes are enlarged. The mass is confirmed by mammography and needle biopsy. A test to show the level of expression of which of the following antigens would assist in determining susceptibility of the tumor to trastuzumab?

A.   CD20

B.   CD52

C.   Epidermal growth factor receptor (EGFR)

D.   HER2/neu

E.   Vascular endothelial growth factor (VEGF)

7. A 78-year-old male patient has hepatocellular carcinoma. The tumor is unresectable due to portal vein invasion. Sorafenib tosylate is a multiple tyrosine kinase inhibitor used in advanced kidney or bladder cancer that can increase survival by 6 to 9 months. What is the advantage of inhibiting multiple kinases as opposed to a single kinase?

A.   To account for genetic differences in kinases

B.   To inhibit both angiogenesis and tumor cell growth

C.   To inhibit multiple stages of blood vessel growth

D.   To inhibit multiple sites on the Raf serine/threonine kinase

E.   To ensure the drug is effective in both slow and rapid acetylators

8. A 60-year-old man reports difficulty starting his urination and poor urinary stream for the last 4 months. A digital rectal exam of the prostate reveals masses in both lobes. Serum prostate-specific antigen (PSA) is elevated. The patient is referred to a urologist, who conducts a needle biopsy and histologic grading. The decision is made to use a combination of radiotherapy and hormonal therapy. Why is flutamide administered prior to leuprolide?

A.   It prevents the breakdown of leuprolide by liver cytochrome P-450 enzymes.

B.   A positive response to flutamide may obviate the need for giving leuprolide.

C.   It induces receptor desensitization.

D.   It increases absorption from the gastrointestinal tract.

E.   It blocks the effect of the initial surge of hormones produced by leuprolide.

9. A 29-year-old patient has a lymph node biopsy and is diagnosed as having Hodgkin lymphoma, nodular sclerosis type. A course of therapy with doxorubicin, bleomycin, vinblastine, and dacarbazine is recommended. Before beginning chemotherapy, what steps might be taken to alleviate the most common acute toxicity of this regimen?

A.   Use behavioral modification therapy.

B.   Administer morphine as needed after the chemotherapy session.

C.   Administer ondansetron prophylactically

D.   Soak the patient's arm in Epsom salts.

E.   Administer milk of magnesia.

10. A 28-year-old female patient had ingested a toxic overdose of phencyclidine, a weak base. Because of the severity of her symptoms, you rightfully conclude that almost all of the phencyclidine had been absorbed by the time she was brought to the emergency room. Which of the following actions may be effective?

A.   Induce vomiting with apomorphine.

B.   Alkalinize the urine with sodium bicarbonate.

C.   Perform hemoperfusion.

D.   Acidify the urine with ammonium chloride.

E.   Perform gastric lavage with charcoal.

11. A patient who has received multiple blood transfusions may require chelation therapy with which of the following?

A.   Dimercaprol

B.   Succimer

C.   Ethylenediaminetetraacetic acid (EDTA)

D.   Trientine

E.   Deferoxamine

12. A person is brought to the hospital in a coma with severely depressed respiration, no response to pain, and small pupils. A friend says the patient took some kind of drug, or drugs, but he does not know what kind. An injection of naloxone makes the pupils larger and only slightly improves respiration. Injecting more naloxone causes no further change. Of the following, what is the most probable cause of this reaction to naloxone?

A.   This is probably a mixed overdose from an opioid plus another drug.

B.   B. The patient probably is also an amphetamine user, is tolerant to amphetamine, and would thus be cross-tolerant to the respiratory stimulation caused by naloxone.

C.   C. This is an addict who is in a postictal state, having just suffered an opioid withdrawal convulsion.

13. A college student is brought to the emergency room. She is unconscious, with no response to painful stimuli. Deep tendon reflexes are hyperactive. Respirations are 4/min. Blood pressure is 80/50 mm Hg. The skin is cool and cyanotic. Pupils are slightly dilated with sluggish reaction to light. Her roommate reports that the patient took “about 10 or 20” capsules of chloral hydrate and “lots” of pills of codeine. An endotracheal tube is inserted. Gastric washing reveals many partially digested capsules. The resident on duty injects naloxone intravenously. After giving naloxone, respirations are still inadequate. Which one of the following measures is most appropriate to correct respiratory function?

A.   Inject strychnine.

B.   Inject pentylenetetrazol.

C.   Inject dopamine.

D.   Mechanically assist respirations.

E.   Force-feed caffeine.

14. A woman is found unconscious near a bottle hand-labeled “roach poison.” She is having convulsive movements and is covered with urine and feces. In the emergency room, she is cyanotic, has a pulse of 50 beats/min, blood pressure of 70/20 mm Hg, and cold, wet skin. Immediate action should include instituting artificial ventilation and which of the following?

A.   Administering atropine intravenously

B.   Administering edrophonium intravenously

C.   Administering neostigmine intravenously

D.   Ordering an assay of serum cholinesterase activity

E.   Ordering a blood toxicology panel

15. Which of the following agents is useful in treating cyanide toxicity?

A.   Carbon monoxide

B.   Trientine

C.   Sodium nitrite/sodium thiosulfate

D.   Pralidoxime

E.   Dimercaprol

Answers and Explanations

1. D Cisplatin concentrates in the kidneys and produces renal toxicity (p. 370).

A–C, E None of the other agents concentrate in the kidney and therefore do not produce renal toxicity.

2. B Methotrexate is a folic acid analogue that competitively inhibits dihydrofolate reductase and thus suppresses the production of purine and thymine nucleotides (p. 370).

A Fluorouracil is a pyrimidine analogue that inhibits thymidylate synthesis.

C Mechlorethamine is an alkylating agent that binds covalently to guanine nucleotides of DNA, cross-linking DNA strands, thus preventing DNA replication and transcription.

D Dactinomycin intercalates between G-C pairs in double-stranded DNA and inhibits DNA-directed RNA synthesis.

E Vincristine is an antimitotic agent that inhibits cell development.

3. A Leucovorin is folinic acid, the active form of folic acid that does not require dihydrofolate reductase. Leucovorin enhances the efficacy of fluorouracil, possibly by inhibiting thymidylate synthase. When given with methotrexate, leucovorin is used to provide normal cells with the active form of folic acid (p. 371).

4. A Doxorubicin is taken up by cardiac muscle, leading to oxidative damage of heart muscle and refractory congestive heart failure (p. 373).

B–E These agents are not cardiotoxic.

5. C Etoposide inhibits DNA topoisomerase II, which acts on single-stranded DNA to cause strand breakage (p. 374).

A Cyclophosphamide is a widely used alkylating agent that binds covalently to guanine nucleotides of DNA, cross-linking DNA strands, thus preventing DNA replication and transcription.

B Methotrexate is a folic acid analogue that competitively inhibits dihydrofolate reductase and thus suppresses the production of purine and thymine nucleotides.

D Leuprolide is a gonadotropin-releasing hormone (GnRH) agonist that desensitizes pituitary GnRH receptors and inhibits gonadotropin (follicle-stimulating hormone and luteinizing hormone) release.

E Fluorouracil is a pyrimidine analogue that inhibits thymidylate synthesis.

6. D Trastuzumab is a monoclonal antibody directed against HER2/neu. HER2/neu is a member of the epidermal growth factor family of cell membrane receptors. Trastuzumab is approved for treatment of metastatic breast cancer when HER2/neu is overexpressed (p. 377).

A Rituximab, tositumomab, 131I-tositumomab, 111In ibritumomab, and 90Y-ibritumomab tiuxetan bind to CD20, which is found on pre-B and mature B lymphocytes.

B Alemtuzumab binds to CD52, which is present on the surface of essentially all B and T lymphocytes, a majority of monocytes, macrophages, and NK cells, as well as a subpopulation of granulocytes.

B Alemtuzumab binds to CD52, which is present on the surface of essentially all B and T lymphocytes, a majority of monocytes, macrophages, and NK cells, as well as a subpopulation of granulocytes.

B Alemtuzumab binds to CD52, which is present on the surface of essentially all B and T lymphocytes, a majority of monocytes, macrophages, and NK cells, as well as a subpopulation of granulocytes.

B Alemtuzumab binds to CD52, which is present on the surface of essentially all B and T lymphocytes, a majority of monocytes, macrophages, and NK cells, as well as a subpopulation of granulocytes.

C Cetuximab binds to EGFR, which has been detected in many human cancers, including those of the colon and rectum.C Cetuximab binds to EGFR, which has been detected in many human cancers, including those of the colon and rectum.C Cetuximab binds to EGFR, which has been detected in many human cancers, including those of the colon and rectum.C Cetuximab binds to EGFR, which has been detected in many human cancers, including those of the colon and rectum.

B Alemtuzumab binds to CD52, which is present on the surface of essentially all B and T lymphocytes, a majority of monocytes, macrophages, and NK cells, as well as a subpopulation of granulocytes.

C Cetuximab binds to EGFR, which has been detected in many human cancers, including those of the colon and rectum.E Bevacizumab binds to VEGF and prevents the proliferation of endothelial cells and formation of new blood vessels, thus starving tumors of their blood supply.

7. B Sorafenib inhibits vascular endothelial growth factor receptor and platelet-derived growth factor receptor to inhibit angiogenesis and the Raf serine/threonine kinases that mediate growth and differentiation of tumor cells (p. 379).

8. E The growth of prostate cells is stimulated by testosterone. Production of testosterone by Leydig cells of the testes is increased by luteinizing hormone (LH) released from the pituitary. The release of LH is regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus. Leuprolide is a GnRH-receptor agonist that initially stimulates and then desensitizes pituitary GnRH receptors. This leads to decreased gonadotropin release, decreased testosterone production, decreased prostate growth, and a beneficial effect in prostate cancer. The initial stimulation produced by leuprolide results in an initial surge in LH and testosterone release, which would have an adverse effect on prostate cancer. To block the effects of this initial surge of hormones, flutamide is given. Flutamide is a competitive antagonist of testosterone for binding to androgen receptors in the prostate gland. By doing so, it prevents them from stimulating the prostate cancer cells to grow (pp. 382 and 383).

9. C Nausea and vomiting are the most common side effects of this chemotherapy. Of the listed choices, the only one that could be used to address nausea and vomiting is ondansetron, which is a 5-HT3 receptor antagonist.

10. D Weak bases are excreted faster (“ion-trapped”) if the urine is acidified with ammonium chloride.

A, E Inducing vomiting with apomorphine and performing gastric lavage with charcoal are unlikely to be effective, as the drug has already been absorbed.

B Alkalinization of the urine with sodium bicarbonate will retard elimination because phencyclidine is a weak base.

C Phencyclidine is not effectively extracted by hemoperfusion.

11. E Multiple drug transfusions can lead to iron poisoning. Deferoxamine specifically chelates iron and promotes its excretion (p. 390).

A Dimercaprol is an effective treatment following poisoning by arsenic, gold, lead, and mercury.

B Succimer is used for lead poisoning.

C Calcium disodium EDTA is used for lead poisoning.

D Trientine is a copper chelating agent.

12. A Depressed respiration, nociception, and miosis are symptoms of opiate poisoning. As a competitive antagonist of opiates, naloxone should block all of the effects of opiates, with increasing effectiveness at higher doses. The lack of further effect of naloxone suggests multiple drug use.

B–C The other possibilities are not indicated by the response to naloxone.

13. D Although naloxone will block the effects of codeine, it will not block the effects of chloral hydrate, a central nervous system depressant drug. Because there are no specific antidotes for chloral hydrate, life support measures, such as mechanical assistance of respiration, must be taken.

A Strychnine is a pesticide agent that acts by inhibiting glycine. This agent causes seizures and contractions of voluntary muscle that lead to respiratory paralysis.

B Pentylenetetrazol is an experimental drug used to induce convulsions.

C, E Neither dopamine nor caffeine would be expected to have a benefit here.

14. A These are symptoms of organophosphate poisoning. Atropine is a muscarinic receptor antagonist given to relieve the overactivation of muscarinic receptors (p. 391).

B, C Edrophonium and neostigmine are acetylcholinesterase inhibitors and would worsen the symptoms.

D, E Because this is an emergency situation, you would not have time to wait for laboratory results.

15. C Sodium nitrite produces methemoglobin, which binds cyanide. Sodium thiosulfate increases cyanide metabolism (p. 391).

A Carbon monoxide is a poisonous gas.

B Trientine is a copper chelating agent.

D Pralidoxime is a cholinesterase reactivator used in organophosphate poisoning.

E Dimercaprol is an effective treatment following poisoning by arsenic, gold, lead, and mercury.


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