Pharmacology.
1. A drug, given as a 100-mg single dose, results in a peak plasma concentration of 20 μg/mL. The apparent volume of distribution is (assume a rapid distribution and negligible elimination prior to measuring the peak plasma level):
A. 0.5 L.
B. 1 L.
C. 2 L.
D. 5 L.
E. 10 L.
Answer: D

2. A drug with a half-life of 12 hours is administered by continuous intravenous infusion. How long will it take for the drug to reach 90 percent of its final steady state level?
A. 18 hours.
B. 24 hours.
C. 30 hours.
D. 40 hours.
E. 90 hours.
Answer: D

3. Which of the following results in a doubling of the steady-state concentration of a drug?
A. Doubling the rate of infusion.
B. Maintaining the rate of infusion but doubling the loading dose.
C. Doubling the rate of infusion and doubling the concentration of the infused drug.
D. Tripling the rate of infusion.
E. Quadrupling the rate of infusion.
Answer: A

4. A heart failure patient shows digoxin toxicity. She received 125 mcg as standard dose. Serum levels were reported to be 2ng/mL (2 mcg/L). Target therapeutic level is 0.8ng/mL. What dose should she receive?
A. 25 mcg.
B. 50 mcg.
C. 75 mcg.
D 100 mcg.
E. 125 mcg.
Answer: B

5. The addition of glucuronic acid to a drug:
A. Decreases its water solubility.
B. Usually leads to inactivation of the drug.
C. Is an example of a Phase I reaction.
D. Occurs at the same rate in adults and newborns.
E. Involves cytochrome P450.
Answer: B

6. Drug X produces maximal contraction of cardiac muscle in a manner similar to epinephrine. Drug X is considered to be a(n)
A. Agonist.
B. Partial agonist.
C. Competitive Antagonist.
D. Irreversible antagonist.
E. Inverse agonist.
Answer: A

7. Which of the following statements is correct?
A. If 10 mg of Drug A produces the same response as 100 mg of Drug B, Drug A is more efficacious than Drug B.
B. The greater the efficacy, the greater the potency of a drug.
C. In selecting a drug, potency is usually more important than efficacy.
D. A competitive antagonist increases the ED50.
E. Variation in response to a drug among different individuals is most likely to occur with a drug showing a large therapeutic index.
Answer: D

8. Variation in the sensitivity of a population of individuals to increasing doses of a drug is best determined by which of the following?
A. Efficacy.
B. Potency.
C. Therapeutic index.
D. Graded dose–response curve.
E. Quantal dose–response curve.
Answer: E

9. Which of the following statements most accurately describes a system having spare receptors?
A. The number of spare receptors determines the maximum effect.
B. Spare receptors are sequestered in the cytosol.
C. A single drug–receptor interaction results in many cellular response elements being activated.
D. Spare receptors are active even in the absence of agonist.
E. Agonist affinity for spare receptors is less than their affinity for nonspare receptors.
Answer: C

10. A patient was given a 200 mg dose of a drug IV, and 100 mg was eliminated during the first two hours. If the drug follows first -order elimination kinetics, how much of the drug will remain 6 hours after its administration?
A. None
B. 25mg
c. SOmg
D. 75mg
E. 100 mg
Answer: B

11. Drugs that are administered IV are
A. Rapidly absorbed
B. Subject to first-pass metabolism
C. 100% bioavailable
D. Rapidly excreted by the kidneys
E. Rapidly metabolized by the liver
Answer: C

12. Drugs that are highly bound to albumin:
A. Effectively cross the BBB
B. Are easily filtered at the glomerulus
C. Have a large V d
D. Often contain quaternary nitrogens
E. Can undergo competition with other drugs for albumin binding sites
Answer: E

13. 4ost drugs gain entry to cells by:
A. Passive diffusion with zero-order kinetics
B. Passive diffusion with first-order kinetics
C. Active transport with zero-order kinetics
D. Active transport with first -order kinetics
E. Passive diffusion through membrane pores
Answer:B

14. A subject in whom the renal clearance of inulin is 120 mL/min is given a drug, the clearance of which is found to be 18 mL/min. If the drug is 40% plasma protein bound, how much filtered drug must be reabsorbed in the renal tubules?
A. None
B. 18 mL/min
c. 36 mL!min
D. 54 mL/min
E. 72 mL/min
Answer: D

15. If a drug is known to be distributed into total body water, what dose (mg) is needed to obtain an initial plasma level of 5 mg/L in a patient weighing
70 kg?
A. 210
B. 150
c. 110
D. 50
E. 35
Answer:A

16. Which of the following is a phase II drug metabolism reaction associated with a genetic polymorphism?
A. Acetylation
B. Glucuronidation
C. Oxidation
D. Reduction
E. Glutathione conjugation
Answer: A

17. A woman is taking oral contraceptives (OCs). Which of the following drugs is unlikely to reduce the effectiveness of the OCs?
A. Carbamazepine
B. Phenytoin
c. Ketoconazole
D. Phenobarbital
E. Rifampin
Answer: C

18. The data presented in the figure below show that:

A. Drugs A and B have equal efficacy
B. Drug B and C have equal efficacy
C. Drug B is a partial agonist
D. Drugs A and C have the same affinity and efficacy
E. Drugs A and B have equal potency
Answer:A

19. A 500-mg dose of a drug has therapeutic efficacy for 6 h. If the half-life of the drug is 8 h, for how long would a 1-g dose be effective?
A. 8h
B. 12 h
c. 14 h
D. 16 h
E. 24h
Answer: