FPGEE MCQ Exam Flashcards

A patient with severe renal impairment (CrCl < 30 mL/min) requires anticoagulation. Which agent requires the MOST significant dose adjustment?

Answer: Dabigatran

Dabigatran is 80% renally eliminated and is contraindicated in severe renal impairment (CrCl < 30 mL/min).

Which pharmacokinetic parameter is most affected by hepatic enzyme induction by rifampin?

Answer: Oral bioavailability and hepatic clearance

Rifampin induces CYP450 enzymes, increasing hepatic metabolism and reducing oral bioavailability of susceptible drugs.

A prescriber orders aminoglycoside therapy. Which parameter best correlates with aminoglycoside efficacy?

Answer: Peak/MIC ratio

Aminoglycosides exhibit concentration-dependent killing; their efficacy correlates best with the peak concentration to MIC ratio.

Which receptor mechanism is responsible for the therapeutic effect of benzodiazepines in treating anxiety?

Answer: Positive allosteric modulation of GABA-A receptors

Benzodiazepines enhance the effect of GABA at GABA-A receptors by positive allosteric modulation, increasing chloride ion conductance.

A patient on methotrexate presents with mucositis. Which agent is used to rescue from methotrexate toxicity?

Answer: Leucovorin (folinic acid)

Leucovorin (folinic acid) bypasses the dihydrofolate reductase enzyme blocked by methotrexate, restoring folate function.

According to USP , what is the beyond-use date for a high-risk compounded sterile preparation stored at room temperature?

Answer: 24 hours

Under USP , high-risk compounded sterile preparations stored at room temperature must be used within 24 hours.

Which drug class is associated with development of drug-induced lupus erythematosus?

Answer: Hydralazine and procainamide

Hydralazine, procainamide, and isoniazid are classic causes of drug-induced lupus erythematosus.

A 65-year-old patient requires a loading dose of digoxin. Which factor most significantly affects the volume of distribution (Vd) of digoxin?

Answer: Lean body weight and tissue binding

Digoxin has a very large Vd (~7 L/kg) due to extensive binding to skeletal muscle and other tissues; lean body weight is used to dose it.

Which enzyme is responsible for the first-pass metabolism of morphine to morphine-6-glucuronide?

Answer: UGT2B7 (UDP-glucuronosyltransferase)

Morphine undergoes extensive glucuronidation by UGT2B7 in the liver and intestinal wall, producing morphine-6-glucuronide (active) and morphine-3-glucuronide.

A patient taking phenytoin for seizures is started on valproic acid. What is the expected net effect on phenytoin?

Answer: Decreased total phenytoin with possible increased free phenytoin levels

Valproic acid displaces phenytoin from protein binding (decreasing total levels) while also inhibiting its metabolism, often raising free (active) phenytoin.

Under the OBRA '90 regulations, pharmacists are required to perform which activities when dispensing medications to Medicaid patients?

Answer: Drug utilization review (DUR), patient counseling, and maintaining medication records

OBRA '90 mandates prospective DUR, patient counseling offers, and maintenance of patient medication records for Medicaid outpatient prescriptions.

Which antihypertensive agent is absolutely contraindicated in bilateral renal artery stenosis?

Answer: Lisinopril

ACE inhibitors like lisinopril block angiotensin II–mediated efferent arteriolar constriction, which is the compensatory mechanism maintaining GFR in bilateral renal artery stenosis.

A patient develops QT prolongation after starting a new antibiotic. Which agent is MOST likely responsible?

Answer: Azithromycin

Azithromycin (and other macrolides) block hERG potassium channels, prolonging the QT interval and increasing the risk of Torsades de Pointes.

Which parameter describes the fraction of a drug excreted unchanged in the urine?

Answer: Fraction excreted renally (fe)

The fraction excreted renally (fe) represents the proportion of absorbed drug eliminated unchanged by the kidneys and determines how much renal impairment affects drug clearance.

A pharmacist receives a prescription for oxycodone 5 mg #30. The DEA schedule of oxycodone requires how many days' supply maximum per prescription in most US states?

Answer: No federal day-supply limit exists for Schedule II

Federally, the DEA does not impose a day-supply limit on Schedule II prescriptions; however, individual states may set their own limits.

Which mechanism explains the therapeutic action of metformin in type 2 diabetes?

Answer: Activates AMPK, reducing hepatic glucose output

Metformin primarily activates AMP-activated protein kinase (AMPK), suppressing hepatic gluconeogenesis and glycogenolysis to lower blood glucose.

A patient on warfarin begins taking high-dose vitamin E supplements. What is the expected effect on INR?

Answer: Increased INR due to inhibition of vitamin K-dependent clotting factors

High-dose vitamin E impairs vitamin K–dependent carboxylation of clotting factors II, VII, IX, and X, potentiating warfarin's anticoagulant effect and raising INR.

Which isomer of albuterol is responsible for its bronchodilatory therapeutic effect?

Answer: R-albuterol (levalbuterol)

R-albuterol (levalbuterol) is the eutomer that binds beta-2 receptors and causes bronchodilation; S-albuterol may contribute to bronchoconstriction.

A patient with Parkinson's disease taking levodopa/carbidopa develops end-of-dose wearing off. Which add-on agent BEST extends levodopa effect?

Answer: Entacapone (COMT inhibitor)

Entacapone inhibits COMT, preventing peripheral breakdown of levodopa and extending its duration of action to reduce wearing-off.

What is the primary mechanism of resistance to beta-lactam antibiotics in MRSA?

Answer: Altered penicillin-binding protein (PBP2a) encoded by mecA gene

MRSA resistance is mediated by mecA gene–encoded PBP2a, a modified penicillin-binding protein with low affinity for all beta-lactam antibiotics.