NURSING PHARMACOLOGY COMPREHENSIVE STUDY GUIDE

PRACTICE QUESTIONS MC = Select ONE best answer MR = Select ALL that apply Q1 Question 1 Multiple Choice Category: Pharmacokinetics A nurse is administering a drug with a narrow therapeutic index. Which pharmacokinetic process has the MOST direct impact on maintaining a drug's plasma concentration within the therapeutic range? A. Absorption via the gastrointestinal tract B. Distribution to peripheral tissues C. Hepatic first-pass metabolism D. Renal elimination and clearance CORRECT ANSWER: D. Renal elimination and clearance Rationale Renal elimination determines how quickly a drug is removed from the body. For drugs with a narrow therapeutic index (e.g., digoxin, lithium, vancomycin), impaired renal clearance leads to drug accumulation and toxicity. Nurses must monitor renal function (creatinine clearance, BUN) and adjust dosing accordingly. While first-pass metabolism affects bioavailability, renal clearance is the primary determinant of steady-state plasma concentration for most narrow-index drugs. Nursing Implication: Always assess renal function before administering narrow-therapeutic-index drugs. Dose reduction or extended intervals are required in renal impairment. Q2 Question 2 Multiple Choice Category: Pharmacokinetics A patient takes Drug A and Drug B together. Drug B inhibits CYP3A4, the primary enzyme responsible for metabolizing Drug A. What is the MOST likely outcome for Drug A? A. Decreased plasma concentration of Drug A B. Increased plasma concentration of Drug A with risk of toxicity C. Faster elimination of Drug A from the body D. Reduced bioavailability of Drug A CORRECT ANSWER: B. Increased plasma concentration of Drug A with risk of toxicity Rationale Enzyme inhibition reduces the metabolism of the substrate drug (Drug A), causing it to accumulate in the plasma. This is a major source of drug-drug interactions. Common CYP3A4 inhibitors include azole antifungals (ketoconazole), macrolide antibiotics (erythromycin), and HIV protease inhibitors. The opposite effect — enzyme induction — would accelerate Drug A's metabolism and reduce its plasma levels. Nursing Implication: Review all concurrent medications for CYP450 interactions before administering new drugs. Alert the prescriber if an inhibitor or inducer is identified. Q3 Question 3 Multiple Choice Category: Pharmacokinetics A patient with severe hepatic cirrhosis is prescribed a medication that undergoes extensive first-pass metabolism. How should the nurse anticipate the prescriber will adjust the dose? A. Increase the dose to overcome reduced absorption B. Administer the drug intravenously to bypass the liver entirely C. Reduce the oral dose to prevent toxic plasma levels D. No adjustment is needed; first-pass metabolism occurs in the gut wall only CORRECT ANSWER: C. Reduce the oral dose to prevent toxic plasma levels Rationale First-pass metabolism occurs primarily in the liver. In hepatic cirrhosis, liver function is impaired, so less of the drug is metabolized before reaching systemic circulation. This results in higher bioavailability of the drug, increasing the risk of toxicity. The dose should be reduced. Morphine, propranolol, and lidocaine are examples of drugs with high first-pass effects that require dose reduction in liver disease. Nursing Implication: Assess liver function tests (ALT, AST, bilirubin, albumin) before dosing. Use lower starting doses in patients with hepatic impairment. Q4 Question 4 Multiple Choice Category: Pharmacodynamics A patient receives naloxone after a morphine overdose and regains consciousness rapidly. Which pharmacodynamic mechanism BEST explains naloxone's action? A. Naloxone stimulates opioid receptors to reverse respiratory depression B. Naloxone is a competitive antagonist at mu-opioid receptors C. Naloxone inhibits CYP enzymes to clear morphine rapidly D. Naloxone acts as a partial agonist at kappa-opioid receptors CORRECT ANSWER: B. Naloxone is a competitive antagonist at mu-opioid receptors Rationale Naloxone (Narcan) is a pure opioid antagonist with high affinity for mu-opioid receptors. It competitively displaces opioids like morphine from receptor binding sites without activating them, rapidly reversing sedation, respiratory depression, and analgesia. Its short half-life (~60–90 min) means repeat dosing may be needed for long-acting opioids. Naloxone has no intrinsic agonist activity. Nursing Implication: Monitor patients closely after naloxone administration; re-sedation can occur as naloxone wears off. Have repeat doses available and be prepared to support ventilation. Q5 Question 5 Multiple Choice Category: Pharmacodynamics Which term BEST describes a drug that binds to a receptor, produces a submaximal response, and also blocks full agonists from binding? A. Full agonist B. Competitive antagonist C. Partial agonist D. Inverse agonist CORRECT ANSWER: C. Partial agonist Rationale A partial agonist has affinity for the receptor and produces a response, but cannot produce the maximum effect a full agonist can (lower intrinsic efficacy). When a full agonist is present, the partial agonist competes for the same receptor and reduces the overall effect — acting like an antagonist. Buprenorphine is a classic example: it partially activates mu-opioid receptors and blocks heroin from producing a full effect. Nursing Implication: Educate patients on buprenorphine that the drug ceiling effect limits its abuse potential and reduces overdose risk compared to full opioid agonists. Q6 Question 6 Multiple Choice Category: Medication Safety The nurse prepares to administer a medication and notes that the dose ordered is three times the usual recommended dose. What is the nurse's PRIORITY action? A. Administer the medication as ordered since the physician is responsible B. Administer half the dose and document the discrepancy C. Hold the medication and contact the prescriber to clarify the order D. Ask a colleague to verify the dose and administer if they agree CORRECT ANSWER: C. Hold the medication and contact the prescriber to clarify the order Rationale Nurses have an independent duty to verify medication orders for safety. An unusually high dose must be questioned before administration. The nurse should hold the drug and contact the prescriber immediately for clarification. This upholds patient safety and reflects the nurse's scope of professional responsibility. Administering an incorrect dose, even under physician orders, makes the nurse legally and ethically liable. Nursing Implication: Always question orders that deviate significantly from the recommended dosing range. Use clinical judgment and institutional resources (pharmacist, drug references) to verify safety. Q7 Question 7 Multiple Choice Category: Autonomic Pharmacology A patient receives atropine preoperatively. Which assessment finding is CONSISTENT with the expected therapeutic effect of this medication? A. Heart rate of 48 beats/min B. Excessive salivation and lacrimation C. Heart rate of 96 beats/min and dry mouth D. Bradycardia and bronchospasm CORRECT ANSWER: C. Heart rate of 96 beats/min and dry mouth Rationale Atropine is a muscarinic (anticholinergic) antagonist. By blocking acetylcholine at muscarinic receptors, it increases heart rate (blocks vagal tone on the SA node) and reduces secretions (dry mouth, decreased airway secretions). These are desired effects when given preoperatively to reduce airway secretions and prevent bradycardia during intubation. The other options reflect cholinergic (parasympathetic) stimulation. Nursing Implication: Assess for urinary retention, constipation, blurred vision, and confusion — adverse anticholinergic effects especially in elderly patients. Q8 Question 8 Multiple Choice Category: Autonomic Pharmacology A patient with heart failure receives metoprolol succinate. The nurse understands the drug works primarily by: A. Blocking alpha-1 receptors in peripheral blood vessels B. Selectively blocking beta-1 receptors in the heart C. Stimulating beta-2 receptors to cause vasodilation D. Inhibiting angiotensin-converting enzyme CORRECT ANSWER: B. Selectively blocking beta-1 receptors in the heart Rationale Metoprolol is a cardioselective beta-1 adrenergic blocker. In heart failure, excess catecholamines overstimulate the failing heart, causing further damage. By blocking beta-1 receptors, metoprolol reduces heart rate, contractility, and oxygen demand, improving long-term cardiac remodeling and outcomes. Its selectivity for beta-1 (over beta-2) reduces the risk of bronchospasm compared to non-selective beta-blockers. Nursing Implication: Monitor HR and BP before each dose. Hold if HR 60 bpm or SBP 90 mmHg per protocol. Caution in patients with COPD even with beta-1 selective agents. Q9 Question 9 Multiple Choice Category: Cardiovascular Drugs A patient taking warfarin is started on amiodarone for atrial fibrillation. Which laboratory finding requires IMMEDIATE nursing action? A. INR of 2.1 B. INR of 5.8 with bleeding gums C. Serum potassium of 3.8 mEq/L D. Heart rate of 72 beats/min CORRECT ANSWER: B. INR of 5.8 with bleeding gums Rationale Amiodarone strongly inhibits CYP2C9, the enzyme that metabolizes warfarin (S-enantiomer). This interaction raises the INR significantly, increasing hemorrhage risk. An INR of 5.8 with active bleeding is a medical emergency requiring immediate intervention: hold warfarin, notify prescriber, and prepare for possible reversal with vitamin K or fresh frozen plasma. The therapeutic INR range for most indications is 2.0–3.0. Nursing Implication: When amiodarone is added to warfarin therapy, anticipate warfarin dose reduction (often 30–50%). Monitor INR frequently during initiation. Educate patients on bleeding signs. Q10 Question 10 Multiple Choice Category: Cardiovascular Drugs A patient with hypertension is prescribed lisinopril. The patient calls the clinic reporting a persistent dry cough for 2 weeks. The nurse CORRECTLY interprets this as: A. A sign of worsening heart failure requiring diuretic therapy B. An expected, common adverse effect of ACE inhibitors C. An allergic reaction requiring epinephrine D. A sign of bronchitis unrelated to the medication CORRECT ANSWER: B. An expected, common adverse effect of ACE inhibitors Rationale A persistent dry, nonproductive cough affects 5–20% of patients on ACE inhibitors (lisinopril, enalapril, ramipril). It results from accumulation of bradykinin and substance P in the lung tissue, which ACE normally degrades. This is not allergic in origin and does not respond to cough suppressants. The patient should be switched to an ARB (e.g., losartan), which does not affect bradykinin levels. Nursing Implication: Educate patients about this common side effect at initiation. Reassure them it is not dangerous but advise them to report it so an alternative class can be prescribed. Q11 Question 11 Multiple Response Category: Cardiovascular Drugs A nurse is teaching a patient newly prescribed atorvastatin (Lipitor). Which instructions should the nurse include? Select ALL that apply. A. Take the medication at bedtime for maximum effect B. Avoid large quantities of grapefruit juice C. Report unexplained muscle pain, weakness, or dark urine immediately D. The medication can be discontinued once cholesterol is normal E. Routine liver function monitoring may be recommended F. Alcohol in moderation has no interaction with statins CORRECT ANSWER: B. Avoid grapefruit juice | C. Report muscle symptoms | E. Monitor liver function Rationale Grapefruit juice inhibits CYP3A4, increasing statin plasma levels and myopathy risk. Myopathy and rhabdomyolysis (evidenced by muscle pain and dark urine — myoglobinuria) are serious adverse effects requiring immediate reporting. Liver function monitoring (ALT/AST) is recommended. Atorvastatin is dosed at any time of day (not specifically at bedtime, unlike some statins like simvastatin). Statins must be continued lifelong as cholesterol will rebound if stopped. Alcohol can increase hepatotoxicity risk and is not safe. Nursing Implication: Emphasize that statins are a long-term commitment. Screen for muscle symptoms at each visit. Check baseline and periodic LFTs. Q12 Question 12 Multiple Choice Category: Cardiovascular Drugs A patient in the emergency department presents with bradycardia (HR 38 bpm) and hypotension after suspected digoxin toxicity. Which assessment finding would the nurse MOST expect to see? A. Serum digoxin level of 0.8 ng/mL B. Hyperkalemia and nausea/vomiting C. Hypokalemia and normal ECG D. Tachycardia and elevated blood pressure CORRECT ANSWER: B. Hyperkalemia and nausea/vomiting Rationale Digoxin toxicity inhibits Na+/K+-ATPase pumps throughout the body. In cardiac cells this leads to life-threatening arrhythmias. Systemic pump inhibition causes potassium to accumulate extracellularly, resulting in hyperkalemia. GI symptoms (nausea, vomiting, anorexia) are often the earliest signs. Visual disturbances (yellow-green halos, blurred vision) also occur. Hypokalemia actually worsens digoxin toxicity by increasing drug binding to Na+/K+-ATPase. The therapeutic range for digoxin is 0.5–0.9 ng/mL. Nursing Implication: Monitor electrolytes (especially K+, Mg2+) and renal function regularly. Teach patients to check pulse before each dose and hold if 60 bpm. Q13 Question 13 Multiple Choice Category: Pain Management A postoperative patient receiving IV morphine reports pain of 8/10. The nurse notes RR of 8 breaths/min, SpO2 of 91%, and pinpoint pupils. The nurse's PRIORITY action is: A. Administer the next scheduled morphine dose as ordered B. Reposition the patient and reassess in 15 minutes C. Hold morphine, apply oxygen, and prepare to administer naloxone D. Contact dietary for the patient's next meal CORRECT ANSWER: C. Hold morphine, apply oxygen, and prepare to administer naloxone Rationale The clinical picture — RR 12, SpO2 94%, and pinpoint pupils — indicates opioid-induced respiratory depression, a life-threatening emergency. Priority actions include: withholding further opioids, providing supplemental oxygen, stimulating the patient, and preparing naloxone. Airway and breathing are always the first priority (ABCs). Administering more morphine would be dangerous and could cause respiratory arrest. Nursing Implication: Assess respiratory status before every opioid dose. Keep naloxone (Narcan) and resuscitation equipment readily available when opioids are administered. Q14 Question 14 Multiple Choice Category: Pain Management Which analgesic approach BEST exemplifies the WHO analgesic ladder's recommendation for a patient with moderate chronic cancer pain not controlled by non-opioids? A. High-dose IV morphine administered as needed B. Addition of a weak opioid (e.g., tramadol) to the non-opioid regimen C. Immediate switch to strong opioids and discontinue all non-opioids D. Restrict all opioids to avoid dependence CORRECT ANSWER: B. Addition of a weak opioid (e.g., tramadol) to the non-opioid regimen Rationale The WHO three-step analgesic ladder recommends a stepwise approach: Step 1 = non-opioids (NSAIDs, acetaminophen) for mild pain; Step 2 = add a weak opioid (codeine, tramadol) for moderate pain; Step 3 = replace with a strong opioid (morphine, oxycodone) for severe pain. Non-opioids are generally continued at each step as they have an additive effect. The goal is around-the-clock dosing rather than PRN administration for chronic pain. Nursing Implication: Evaluate pain at regular intervals using a validated scale. Adjust analgesic regimen stepwise. Address constipation prophylactically when initiating opioids. Q15 Question 15 Multiple Response Category: Pain Management The nurse is caring for a patient receiving long-term opioid therapy. Which interventions should be included in the nursing care plan? Select ALL that apply. A. Administer a stool softener/laxative prophylactically B. Monitor for signs of physical dependence and plan a tapering schedule when discontinuing C. Restrict fluid intake to prevent edema D. Assess pain level using a consistent validated pain scale E. Educate the patient that sedation typically persists throughout treatment F. Monitor respiratory rate before each dose CORRECT ANSWER: A. Laxative prophylaxis | B. Taper when discontinuing | D. Consistent pain assessment | F. Monitor RR Rationale Opioid-induced constipation is universal and does not develop tolerance — laxatives must be given routinely. Physical dependence (not the same as addiction) develops with long-term use; abrupt discontinuation causes withdrawal, so tapering is required. Consistent pain assessment guides dose adjustments. Respiratory depression is the most dangerous adverse effect. Sedation typically diminishes with tolerance after a few days; fluid restriction is not indicated. Nursing Implication: Distinguish between physical dependence (physiologic), tolerance (need for higher doses), and addiction (compulsive misuse). Educate patients and families on these differences. Q16 Question 16 Multiple Choice Category: Anti-infectives – Antibiotics A patient is prescribed vancomycin IV. The nurse administers the infusion over 15 minutes. Shortly after, the patient develops flushing, pruritus, and erythema of the face, neck, and upper torso. The nurse recognizes this reaction as: A. Anaphylaxis requiring immediate epinephrine B. Red Man Syndrome due to rapid infusion C. A sign of vancomycin nephrotoxi