NAPLEX Quiz: Medication And Allergy History

What this quiz covers

This quiz focuses on Medication And Allergy History, giving you a quick way to practice the rules, question types, and explanations that matter most for NAPLEX.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

Question 1

1. Cyclobenzaprine 10 mg by mouth three times daily as needed (using daily) (correct answer)
2. Metformin 1,000 mg by mouth twice daily
3. Lisinopril 20 mg by mouth daily
4. Metoprolol succinate 25 mg by mouth daily

Explanation: This question tests identification of medication-related causes of dizziness and fall risk in an older adult. The key patient-specific factor is daily use of cyclobenzaprine, a centrally-acting muscle relaxant, in a 59-year-old patient experiencing dizziness and near falls. Cyclobenzaprine (choice A) is the BEST answer because it causes significant CNS depression, sedation, and anticholinergic effects that increase fall risk, especially with regular use and in combination with gabapentin. Metformin (choice B) rarely causes dizziness unless causing hypoglycemia, which is unlikely with an A1c of 6.4%. Lisinopril (choice C) and metoprolol (choice D) can cause orthostatic hypotension but are less likely culprits given stable use. The clinical pearl is that muscle relaxants like cyclobenzaprine are high-risk medications in older adults (Beers Criteria) and should be used sparingly, if at all, due to sedation and fall risk, particularly when combined with other CNS depressants.

Question 2

1. Assume the antibiotic is azithromycin and add it to the profile because it is commonly used for bronchitis
2. Obtain the exact antibiotic name, dose, and start date from the prescriber or dispensing pharmacy because several antibiotics can significantly increase INR with warfarin (correct answer)
3. Increase warfarin to 6 mg by mouth nightly to overcome possible antibiotic-induced changes
4. Stop levothyroxine because it is the most common cause of elevated INR in warfarin patients

Explanation: This question tests management of warfarin drug interactions and the importance of complete medication histories. The key patient-specific factor is a significantly elevated INR (5.6) after starting an unknown antibiotic in a warfarin patient. Obtaining the exact antibiotic information (choice B) is the BEST answer because many antibiotics (fluoroquinolones, macrolides, sulfonamides, metronidazole) can dramatically increase INR through CYP2C9 inhibition or gut flora disruption, and management depends on the specific agent. Assuming it's azithromycin (choice A) is dangerous without verification. Increasing warfarin (choice C) would worsen the supratherapeutic INR. Levothyroxine (choice D) rarely causes significant INR changes at stable doses. The clinical pearl is that antibiotics are among the most common causes of warfarin drug interactions, and INR should be monitored closely during and after antibiotic therapy, with warfarin dose adjustments as needed.

Question 3

1. Recommend starting aspirin 81 mg daily until the exact anticoagulant is confirmed
2. Contact the patient's previous pharmacy and prescribers to obtain a fill history and current active prescriptions (drug, strength, directions, last fill date) (correct answer)
3. Assume the "blood thinner" is warfarin because an INR was provided and add it to the profile
4. Document only the medications the patient can name and defer the rest until the next visit

Explanation: This question tests the pharmacist's role in accurate medication reconciliation for a new patient with incomplete medication history. The key patient-specific factor is the vague recall of medications, including an unspecified 'blood thinner' with an INR of 1.1, alongside comorbidities like atrial fibrillation and chronic kidney disease. Contacting the previous pharmacy and prescribers is the best choice because it provides objective fill history and active prescriptions to ensure safe dispensing and avoid assumptions. Recommending aspirin is inappropriate without confirming the anticoagulant, assuming warfarin ignores other possibilities like direct oral anticoagulants, and documenting only named medications or deferring risks incomplete reconciliation. A transferable clinical pearl is that medication reconciliation should prioritize external verification sources like pharmacies or electronic records when patient recall is unreliable. Pharmacists can use a systematic framework: ask open-ended questions, review available labs, and cross-verify with historical data to build an accurate profile.

Question 4

1. Omeprazole 20 mg daily (correct answer)
2. Atorvastatin 40 mg nightly
3. Sertraline 50 mg daily
4. Clopidogrel 75 mg daily

Explanation: This question tests the identification of pharmacokinetic interactions affecting antiplatelet therapy. The key patient-specific factor is omeprazole use with clopidogrel, as omeprazole inhibits CYP2C19, reducing clopidogrel activation and efficacy post-TIA. Omeprazole requires verification to consider alternatives like pantoprazole with less interaction. Atorvastatin, sertraline, and clopidogrel itself are not the interacting pair here. A transferable clinical pearl is that certain PPIs like omeprazole diminish clopidogrel's antiplatelet effects. Employ a framework: screen for CYP2C19 inhibitors, evaluate alternatives, and recommend switches for high-risk patients.

Question 5

1. Confirm the exact metoprolol formulation (tartrate vs succinate) and dosing frequency with the previous pharmacy or prescription bottles (correct answer)
2. Assume metoprolol is extended-release because it is taken daily and enter metoprolol succinate 50 mg daily
3. Change clopidogrel to prasugrel because it is more effective after stent placement
4. Convert pantoprazole to omeprazole 40 mg daily because they are interchangeable

Explanation: This question tests precise medication reconciliation to distinguish formulations and prevent errors in chronic therapy. The key patient-specific factor is the vague 'metoprolol 50 daily' which could be tartrate (twice daily) or succinate (once daily), impacting efficacy post-stent. Confirming the exact formulation with prior sources is the best choice to ensure appropriate dosing and adherence. Assuming extended-release risks underdosing if tartrate, changing clopidogrel ignores guidelines, and converting pantoprazole is not equivalent. A transferable clinical pearl is that beta-blocker formulations differ in duration, affecting once- versus twice-daily use. Use a framework: clarify ambiguities in patient lists, verify with records, and reconcile for accuracy.

Question 6

1. Possible cross-reactive bronchospasm with nonselective NSAIDs; avoid ibuprofen and other nonselective NSAIDs (correct answer)
2. Penicillin cross-allergy; avoid amoxicillin and cephalexin
3. Photosensitivity from cetirizine; avoid sunlight
4. Serotonin syndrome risk from combining albuterol with cetirizine

Explanation: This question tests the assessment of allergy-related risks in patients with aspirin-exacerbated respiratory disease. The key patient-specific factor is the documented aspirin allergy causing breathing trouble, combined with recent ibuprofen use triggering wheezing in an asthmatic patient. Avoiding ibuprofen and nonselective NSAIDs is the best choice due to cross-reactive cyclooxygenase-1 inhibition risking bronchospasm. Penicillin cross-allergy is unrelated, photosensitivity is not a cetirizine issue, and serotonin syndrome is not relevant here. A transferable clinical pearl is that aspirin-sensitive asthmatics should avoid nonselective NSAIDs but may tolerate selective COX-2 inhibitors. Employ a decision framework: review allergy history, identify cross-reactive agents, and counsel on avoidance to prevent exacerbations.

Question 7

1. Assume the patient is using both basal insulins and document both at 30 units nightly
2. Clarify with the patient and prescribers which basal insulin is actually being used, the current dose, and whether the other product was discontinued to prevent duplicate therapy (correct answer)
3. Convert both basal insulins to insulin NPH 30 units nightly for simplicity
4. Stop metformin because concomitant insulin indicates metformin failure

Explanation: This question tests the prevention of duplicate therapy during medication reconciliation. The key patient-specific factor is the fill history showing both insulin glargine and detemir recently, with patient report of 'a long-acting insulin,' risking overdose if both continued. Clarifying which is active and discontinuing the other is the best choice to ensure safety and avoid errors. Assuming both are used risks toxicity, converting to NPH is inappropriate without indication, and stopping metformin ignores its role. A transferable clinical pearl is that basal insulins are not interchangeable without dose adjustment. Use a framework: reconcile fill history with patient report, confirm with sources, and eliminate duplicates.

Question 8

1. Clarify the nature and timing of the prior reaction and assess severity before dispensing; if unclear or concerning, contact the prescriber for an alternative (correct answer)
2. Dispense as written because childhood rashes are never allergic
3. Automatically substitute to cephalexin 500 mg four times daily without contacting the prescriber
4. Document an allergy to clavulanate because it commonly causes rash

Explanation: This question tests the evaluation of beta-lactam allergy history and safe prescribing practices. The key patient-specific factor is the vague childhood 'penicillin' rash, which may represent intolerance rather than true allergy, especially if non-severe. Clarifying the reaction and assessing before dispensing is the best choice to determine if amoxicillin/clavulanate can be safely trialed or if alternatives are needed. Dispensing without clarification risks reaction, substituting to cephalexin assumes cross-reactivity, and documenting clavulanate allergy is speculative. A transferable clinical pearl is that many reported penicillin allergies are low-risk and can be de-labeled with testing. Employ a decision framework: gather reaction details, classify risk, and collaborate with prescribers for alternatives if high-risk.

Question 9

1. Avoid using ibuprofen regularly while kidney function is still recovering and discuss safer pain options with the prescriber (correct answer)
2. Stop omeprazole immediately because it will inactivate azithromycin
3. Take azithromycin with grapefruit juice to improve absorption
4. Restart hydrochlorothiazide at double the dose to prevent fluid retention after pneumonia

Explanation: This question tests counseling on medication safety post-hospitalization, focusing on drug interactions and contraindications in recovery. The key patient-specific factor is the recent acute kidney injury with elevated serum creatinine and chronic ibuprofen use, which can further impair renal function. Advising to avoid regular ibuprofen and discuss alternatives is the best choice to protect recovering kidneys and prevent worsening. Stopping omeprazole is unnecessary as it does not inactivate azithromycin, taking azithromycin with grapefruit juice may alter absorption unpredictably, and doubling hydrochlorothiazide risks electrolyte imbalances without indication. A transferable clinical pearl is that NSAIDs like ibuprofen should be used cautiously in patients with renal impairment due to prostaglandin inhibition. Employ a framework: review discharge labs, identify high-risk home medications, and prioritize counseling on modifiable risks to optimize outcomes.

Question 10

1. Levofloxacin 750 mg by mouth daily because divalent cations (calcium, iron) can reduce absorption; verify administration timing separation (correct answer)
2. Prednisone 40 mg by mouth daily because multivitamins completely inactivate corticosteroids
3. Albuterol inhaler because ferrous sulfate increases beta-agonist toxicity
4. Ferrous sulfate 325 mg by mouth daily because it causes a dangerous interaction with prednisone leading to acute kidney injury

Explanation: This question tests recognition of chelation interactions between fluoroquinolones and polyvalent cations. The key patient-specific factor is concurrent administration of levofloxacin with multiple sources of divalent/trivalent cations (calcium, iron, multivitamin). Levofloxacin requiring timing verification (choice A) is the BEST answer because polyvalent cations can reduce fluoroquinolone absorption by up to 90% through chelation, requiring 2-hour separation before or 6 hours after cation administration. Multivitamins don't inactivate corticosteroids (choice B). Ferrous sulfate doesn't increase albuterol toxicity (choice C) or cause kidney injury with prednisone (choice D). The clinical pearl is that fluoroquinolones must be separated from calcium, iron, magnesium, aluminum, and zinc supplements by at least 2 hours to ensure adequate absorption, and this interaction is one of the most clinically significant drug-food/supplement interactions.

Question 11

1. Recommend starting levothyroxine 25 mcg by mouth daily based on the elevated TSH
2. Call the patient's previous pharmacy and prescribers to obtain an objective fill history and current doses before entering medications into the profile (correct answer)
3. Assume the "water pill" is furosemide 40 mg by mouth daily and the "heart pill" is carvedilol 25 mg by mouth twice daily
4. Focus only on prescription medications because over-the-counter products do not affect medication reconciliation

Explanation: This question tests the importance of obtaining accurate medication histories in elderly patients with multiple chronic conditions. The key patient-specific factor is a new patient with vague medication descriptions and no medication bottles, making accurate reconciliation impossible. Calling previous pharmacy and prescribers for objective fill history (choice B) is the BEST answer because it provides verified medication names, doses, and adherence patterns essential for safe care. Starting levothyroxine based on TSH alone (choice A) is premature without knowing if she's already on thyroid medication. Making assumptions about generic drug names (choice C) is dangerous as many medications could be described as "water pill" or "heart pill." Ignoring OTC products (choice D) is incorrect as they can cause significant interactions. The clinical pearl is that objective verification through pharmacy records or prescriber offices is essential when patients cannot provide specific medication information, especially in elderly patients with polypharmacy.

Question 12

1. Continue naproxen 220 mg by mouth twice daily because it is safer than acetaminophen with apixaban
2. Avoid nonsteroidal anti-inflammatory drugs and verify with the prescriber before restarting aspirin because of increased bleeding risk with apixaban (correct answer)
3. Stop pantoprazole because it reduces absorption of apixaban
4. Take apixaban only when experiencing palpitations to reduce bleeding risk

Explanation: This question tests management of antiplatelet/anticoagulant therapy after gastrointestinal bleeding. The key patient-specific factor is recent GI bleed in a patient on triple antithrombotic therapy (aspirin, naproxen, apixaban) with coronary stents requiring antiplatelet therapy. Avoiding NSAIDs and verifying before restarting aspirin (choice B) is the BEST answer because NSAIDs significantly increase bleeding risk with anticoagulants, and aspirin decisions require risk-benefit assessment given recent bleed and stent history. Continuing naproxen (choice A) is dangerous as NSAIDs increase GI bleeding risk 2-4 fold with anticoagulants. Stopping pantoprazole (choice C) is incorrect; PPIs don't affect apixaban absorption and provide GI protection. Taking apixaban intermittently (choice D) is dangerous and ineffective for stroke prevention. The clinical pearl is that NSAIDs should be avoided with anticoagulants due to synergistic bleeding risk, and decisions about antiplatelet therapy after bleeding require careful risk-benefit assessment considering both bleeding and thrombotic risks.

Question 13

1. Simvastatin 40 mg nightly (correct answer)
2. Levothyroxine 100 mcg daily
3. Amlodipine 5 mg daily
4. Fluticasone nasal spray 1 spray each nostril daily

Explanation: This question tests the recognition of drug interactions with macrolide antibiotics like clarithromycin. The key patient-specific factor is simvastatin use with clarithromycin, as clarithromycin inhibits CYP3A4, increasing simvastatin levels and rhabdomyolysis risk. Simvastatin requires verification to consider dose reduction or holding during therapy. Levothyroxine, amlodipine, and fluticasone do not have significant interactions with clarithromycin. A transferable clinical pearl is that high-dose simvastatin should be avoided with strong CYP3A4 inhibitors. Use a framework: check for CYP interactions, assess statin intensity, and recommend temporary adjustments.

Question 14

1. Multivitamin daily
2. Amiodarone 200 mg daily (correct answer)
3. Levothyroxine 75 mcg daily
4. Serum creatinine 1.0 mg/dL

Explanation: This question tests the identification of drug interactions impacting warfarin therapy and INR stability. The key patient-specific factor is the elevated INR of 4.6 in a patient taking amiodarone with warfarin, as amiodarone inhibits warfarin metabolism. Amiodarone requires verification because it potently increases warfarin effects, risking bleeding. Multivitamin, levothyroxine, and serum creatinine do not directly cause supratherapeutic INR. A transferable clinical pearl is that amiodarone-warfarin interaction necessitates dose adjustments and frequent INR monitoring. Employ a framework: review INR trends, identify interacting agents, and recommend prescriber consultation for management.

Question 15

1. Dextromethorphan-containing OTC cold product (correct answer)
2. Acetaminophen 500 mg as needed
3. Loratadine 10 mg daily
4. Calcium carbonate antacid as needed

Explanation: This question tests the detection of serotonergic drug interactions leading to serotonin syndrome. The key patient-specific factor is the recent sertraline dose increase combined with dextromethorphan and sumatriptan, which can elevate serotonin levels causing nausea, tremor, and sweating. The dextromethorphan-containing product requires verification as it inhibits serotonin reuptake, heightening syndrome risk. Acetaminophen, loratadine, and calcium carbonate do not contribute to serotonergic effects. A transferable clinical pearl is that combining multiple serotonergic agents, including OTCs, necessitates monitoring for syndrome symptoms. Use a framework: list serotonergic medications, assess cumulative risk, and recommend discontinuation of nonessential contributors.

Question 16

1. Avoid sildenafil while using nitroglycerin due to risk of severe hypotension; counsel on required separation and to seek medical advice before use (correct answer)
2. Take sildenafil with nitroglycerin to improve chest pain relief
3. Stop aspirin because it reduces sildenafil effectiveness
4. Increase atorvastatin to 160 mg nightly when using sildenafil

Explanation: This question tests counseling on critical drug interactions in post-myocardial infarction patients. The key patient-specific factor is the concomitant use of sildenafil and nitroglycerin, which can cause profound hypotension due to phosphodiesterase-5 inhibition potentiating nitrates. Advising avoidance and separation is the best choice to prevent life-threatening hypotension. Taking together worsens risks, stopping aspirin ignores its benefit, and increasing atorvastatin is unnecessary. A transferable clinical pearl is that PDE5 inhibitors require at least 24-hour separation from nitrates. Apply a framework: screen for erectile dysfunction agents, educate on risks, and coordinate with prescribers for alternatives.

Question 17

1. The prior gastrointestinal upset confirms an immunoglobulin E (IgE)-mediated penicillin allergy and requires lifelong avoidance of all beta-lactams
2. The current rash and facial flushing after re-exposure may represent a true hypersensitivity reaction and should be documented with specific symptoms and timing (correct answer)
3. Cetirizine is the most likely cause of the rash and should be added to the allergy list
4. Clavulanate is unrelated to allergy risk, so the medication can be continued without changes

Explanation: This question tests evaluation of evolving allergic reactions and proper documentation of drug allergies. The key patient-specific factor is development of rash and facial flushing after amoxicillin-clavulanate in a patient with prior mild penicillin intolerance. The current reaction potentially representing true hypersensitivity (choice B) is the BEST answer because the new symptoms (rash, flushing) differ from the prior GI upset and could indicate IgE-mediated allergy development, requiring immediate discontinuation and proper documentation. Prior GI upset alone (choice A) doesn't confirm IgE-mediated allergy or predict current reaction severity. Cetirizine (choice C) is unlikely to cause this reaction pattern. Clavulanate (choice D) doesn't negate penicillin allergy risk as amoxicillin is still a beta-lactam. The clinical pearl is that drug allergy presentations can evolve over time, and any new cutaneous or systemic symptoms with re-exposure require careful evaluation, discontinuation, and detailed documentation of reaction type and timing.

Question 18

1. Dextromethorphan-containing cough suppressant due to risk of serotonin syndrome with sertraline (correct answer)
2. Guaifenesin 600 mg by mouth every 12 hours due to risk of QT prolongation with sertraline
3. Saline nasal spray due to risk of hypertensive crisis with amlodipine
4. Acetaminophen 650 mg by mouth every 6 hours as needed due to reduced efficacy of sumatriptan

Explanation: This question tests recognition of serotonin syndrome risk with common over-the-counter cold products. The key patient-specific factor is concurrent use of sertraline (an SSRI) with potential exposure to dextromethorphan in cold/flu products. Dextromethorphan-containing products (choice A) require verification as the BEST answer because dextromethorphan has serotonergic activity and can precipitate serotonin syndrome when combined with SSRIs like sertraline. Guaifenesin (choice B) doesn't cause QT prolongation or interact with sertraline. Saline nasal spray (choice C) has no systemic effects or drug interactions. Acetaminophen (choice D) doesn't affect sumatriptan efficacy. The clinical pearl is that many OTC cold/flu products contain dextromethorphan, which can cause serotonin syndrome with SSRIs, SNRIs, or MAOIs; patients on serotonergic medications should use dextromethorphan-free formulations.

Question 19

1. Advise the patient to stop trimethoprim-sulfamethoxazole and seek urgent evaluation for possible anaphylaxis; document sulfonamide antibiotic allergy with reaction details (correct answer)
2. Advise the patient to continue trimethoprim-sulfamethoxazole and add diphenhydramine 25 mg by mouth every 6 hours as needed for hives
3. Change therapy to sulfadiazine 1 g by mouth every 6 hours because it is a different sulfonamide antibiotic
4. Document the reaction as a penicillin allergy because hives are most commonly caused by beta-lactams

Explanation: This question tests recognition and management of a potential anaphylactic reaction to sulfonamide antibiotics. The key patient-specific factor is the development of hives and lip swelling (angioedema) within 2 hours of trimethoprim-sulfamethoxazole administration in a patient with a documented but unclear sulfa allergy history. Advising immediate discontinuation and urgent evaluation (choice A) is the BEST answer because these symptoms suggest a type I hypersensitivity reaction that could progress to anaphylaxis. Continuing the medication with diphenhydramine (choice B) is dangerous as antihistamines won't prevent anaphylaxis progression. Switching to another sulfonamide (choice C) is contraindicated due to cross-reactivity risk. Documenting as penicillin allergy (choice D) is incorrect and would create inaccurate allergy documentation. The clinical pearl is that any signs of angioedema (lip/tongue swelling) with medication exposure require immediate discontinuation and emergency evaluation, as this can rapidly progress to airway compromise.

Question 20

1. Assume the over-the-counter pain reliever is acetaminophen and counsel to limit to 3,000 mg/day while on warfarin
2. Verify the exact over-the-counter analgesic product and frequency because nonsteroidal anti-inflammatory drugs can increase bleeding risk with warfarin (correct answer)
3. Discontinue warfarin due to the penicillin allergy and switch to rivaroxaban 20 mg by mouth daily
4. Verify whether the patient is taking metoprolol tartrate 50 mg by mouth daily instead of metoprolol succinate

Explanation: This question tests the critical skill of medication reconciliation and identifying potentially dangerous drug interactions in a patient on anticoagulation therapy. The key patient-specific factor is the unknown over-the-counter pain reliever in a patient taking warfarin, which has numerous drug interactions. Verifying the exact over-the-counter analgesic product (choice B) is the BEST answer because NSAIDs significantly increase bleeding risk when combined with warfarin through both pharmacodynamic (antiplatelet effects) and pharmacokinetic (protein binding displacement) mechanisms. Assuming it's acetaminophen (choice A) is dangerous because if it's actually an NSAID, the patient could experience serious bleeding. Discontinuing warfarin due to penicillin allergy (choice C) is incorrect as penicillin allergy doesn't contraindicate warfarin use. Verifying the metoprolol formulation (choice D) is less urgent than addressing the bleeding risk. The clinical pearl is that medication reconciliation must include specific identification of all over-the-counter products, especially in patients on high-risk medications like warfarin.