12 original SNLE questions on pharmacology, each with an explanation for all four options. Part of Nursing Fundamentals, worth 20% of the Saudi Nursing Licensure Examination.
Q01 / 10medium0 correct
Nursing Fundamentalsmediumq007
A patient receiving intravenous vancomycin develops flushing and erythema of the face, neck, and upper torso 20 minutes into the infusion. Blood pressure is 96/58 mmHg. What is the nurse's most appropriate immediate action?
All 12 questions
Every question below, with the reasoning for all four options. Try to answer before you open one.
Pharmacology · medium
A patient receiving intravenous vancomycin develops flushing and erythema of the face, neck, and upper torso 20 minutes into the infusion. Blood pressure is 96/58 mmHg. What is the nurse's most appropriate immediate action?
AAdminister intramuscular epinephrine and call the rapid response team
BContinue the infusion at the same rate and document the reaction
CStop the infusion, give an antihistamine, and resume at a slower rate
DPermanently document vancomycin as a drug allergy in the record
Show the answer and why the others fail
Answer: C. Stop the infusion, give an antihistamine, and resume at a slower rate
A
Epinephrine is reserved for true anaphylaxis with airway compromise or shock. This rate-related histamine reaction resolves with slowing the infusion and antihistamines.
B
Continuing at the same rate allows the histamine release to worsen and the hypotension to deepen; the infusion rate is the modifiable cause.
C — correct
This is vancomycin infusion reaction (formerly red man syndrome), a rate-related non-IgE histamine release. Stopping the infusion, treating with an antihistamine, and resuming more slowly (typically over at least 60 minutes or longer) is the correct management.
D
Labelling this an allergy is inaccurate — it is not IgE-mediated — and wrongly removes an important antibiotic from the patient's future options.
TakeawayVancomycin infusion reaction is rate-dependent histamine release, not a true allergy — stop, treat with antihistamine, then infuse more slowly.
Pharmacology · easy
A physician orders 250 mg of an antibiotic to be given orally. The pharmacy supplies a suspension labeled 125 mg per 5 mL. How many milliliters should the nurse administer?
A2.5 mL
B5 mL
C10 mL
D12.5 mL
Show the answer and why the others fail
Answer: C. 10 mL
A
2.5 mL delivers only 62.5 mg, one quarter of the ordered dose; this inverts the calculation.
B
5 mL delivers only 125 mg, which is half the ordered dose.
C — correct
Using desired over available times quantity: 250 divided by 125, multiplied by 5 mL, equals 10 mL. This delivers exactly the ordered 250 mg.
D
12.5 mL would deliver 312.5 mg, an overdose; this results from misapplying the ratio.
TakeawayDose calculation: (desired dose / available dose) x volume on hand — always double-check the units on the supplied concentration.
Pharmacology · hard
A patient stabilized on warfarin for atrial fibrillation has an INR of 6.5 with no bleeding. Which action should the nurse anticipate?
AWithhold the warfarin doses and recheck the INR
BAdminister protamine sulfate to reverse the anticoagulation
CContinue the usual warfarin dose and recheck the INR in one week
DAdminister intravenous vitamin K 10 mg immediately
Show the answer and why the others fail
Answer: A. Withhold the warfarin doses and recheck the INR
A — correct
For an INR between 4.5 and 10 with no bleeding, guidelines direct the nurse to simply omit doses and recheck the INR, allowing it to drift down as clotting factors are regenerated. Routine vitamin K is specifically advised against in this range because it adds no reduction in bleeding events and risks over-correction.
B
Protamine reverses heparin, not warfarin. It has no meaningful effect on vitamin K-dependent clotting factor depletion.
C
Continuing the dose at an INR of 6.5 leaves the patient at substantial risk of spontaneous major bleeding for another week.
D
High-dose IV vitamin K belongs to the management of major or life-threatening bleeding, where it is given together with four-factor prothrombin complex concentrate — the PCC provides the rapid factor replacement, while vitamin K alone takes hours and cannot achieve urgent reversal. In a non-bleeding patient it also produces prolonged warfarin resistance.
TakeawayAn INR of 4.5 to 10 without bleeding is managed by holding warfarin and rechecking the INR, not by giving vitamin K. Low-dose oral vitamin K is considered once the INR exceeds 10, and four-factor PCC plus IV vitamin K is reserved for major bleeding.
Pharmacology · easy
A nurse is preparing to administer a prescribed dose of 10 units of insulin lispro and 20 units of insulin glargine subcutaneously to a patient with diabetes mellitus. Which of the following actions should the nurse take?
AAdminister the insulin lispro and insulin glargine as separate injections.
BDraw up the insulin lispro first, then the insulin glargine in the same syringe.
CDraw up the insulin glargine first, then the insulin lispro in the same syringe.
DGently roll the insulin glargine vial between the palms before drawing up.
Show the answer and why the others fail
Answer: A. Administer the insulin lispro and insulin glargine as separate injections.
A — correct
Insulin glargine is a long-acting analog that must be given separately from other insulins to prevent incompatibility and ensure proper absorption profiles.
B
Insulin glargine is not compatible with other insulins; mixing can cause precipitation and alter absorption, so it should never be mixed in the same syringe.
C
Regardless of the order, insulin glargine should not be mixed with other insulins due to the risk of altering its pharmacokinetics.
D
Insulin glargine is a clear solution that does not require resuspension; rolling is only necessary for cloudy insulins such as NPH.
TakeawayInsulin glargine is a long-acting analog that is a clear solution and must not be mixed with other insulins; administer separate injections.
Pharmacology · medium
A 28-year-old patient with schizophrenia has been taking haloperidol 5 mg twice daily for 2 days. The patient suddenly develops sustained neck twisting, protrusion of the tongue, and difficulty speaking. The patient has a PRN order for benztropine 2 mg IV. Which action should the nurse take first?
AAdminister the prescribed intravenous benztropine.
BWithhold the next dose of haloperidol and notify the physician.
CReassure the patient that this is a common, harmless side effect.
DApply warm compresses to the neck and encourage relaxation.
Show the answer and why the others fail
Answer: A. Administer the prescribed intravenous benztropine.
A — correct
The patient is exhibiting an acute dystonic reaction, a known extrapyramidal side effect of haloperidol. The priority is to administer the prescribed anticholinergic intravenously for rapid relief, especially given the potential for airway compromise.
B
While the haloperidol should be held and the physician notified, the immediate priority is to relieve the patient's acute muscle spasms by administering the prescribed anticholinergic.
C
Acute dystonia is distressing and can compromise the airway; reassurance alone does not address the underlying muscle spasm and delays necessary treatment.
D
Warm compresses and relaxation are ineffective for acute dystonia, which is caused by dopamine blockade and requires pharmacological intervention.
TakeawayAcute dystonic reactions to antipsychotics are treated immediately with anticholinergic agents such as benztropine; intravenous administration is preferred for rapid reversal, especially when airway compromise is possible.
Pharmacology · easy
A nurse is preparing to administer a prescribed mixture of NPH and regular insulin to a patient with type 1 diabetes. Which action should the nurse take first?
AGently roll the NPH vial between the palms to resuspend the insulin.
BInject air into the NPH vial before injecting air into the regular vial.
CDraw up the regular insulin into the syringe before the NPH insulin.
DShake the NPH vial vigorously to ensure the insulin is well mixed.
Show the answer and why the others fail
Answer: A. Gently roll the NPH vial between the palms to resuspend the insulin.
A — correct
Gently rolling the NPH vial resuspends the insulin without creating foam or bubbles, which can cause inaccurate dosing.
B
Injecting air into the vials is performed after resuspending the NPH insulin and cleaning the vial tops; it is not the first step.
C
Drawing up insulin occurs after resuspending the NPH and injecting air; regular insulin is drawn first to avoid contaminating the regular vial.
D
Shaking creates foam and bubbles, leading to inaccurate dosing; NPH should be gently rolled, not shaken.
TakeawayWhen a mixture of NPH and regular insulin is prescribed, the first step is to gently roll the NPH vial between the palms to resuspend the insulin without creating foam or bubbles, which can cause inaccurate dosing. Then inject air into the NPH vial, then the regular vial, and draw up the regular insulin first to prevent contamination. Note: Current guidelines often recommend separate injections to ensure predictable absorption, but this procedure is used when a mixture is specifically prescribed.
Pharmacology · easy
A nurse is preparing to administer a prescribed mixture of NPH insulin and regular insulin to a patient with diabetes mellitus. The mixture is not available as a premixed formulation, so the nurse must mix the insulins from separate vials. Which action should the nurse take?
AShake the NPH insulin vial vigorously before drawing up the dose.
BDraw up the regular insulin first, then the NPH insulin.
CWait at least 30 minutes after mixing before administering the injection.
DDraw up the NPH insulin first, then the regular insulin.
Show the answer and why the others fail
Answer: B. Draw up the regular insulin first, then the NPH insulin.
A
NPH insulin should be gently rolled between the palms to resuspend the particles; vigorous shaking can cause frothing and inaccurate dosing.
B — correct
Drawing up the clear (regular) insulin first prevents contamination of the regular insulin vial with NPH insulin, which could alter the action of future doses drawn from that vial.
C
The mixed insulin should be administered immediately to prevent the regular insulin from binding to the NPH insulin, which would reduce its availability.
D
Drawing up the cloudy (NPH) insulin first risks introducing NPH into the regular insulin vial, contaminating it and potentially affecting the onset and peak of subsequent doses.
TakeawayWhen mixing insulins, always draw up the clear (regular) insulin first to avoid contaminating the multi-dose vial. Premixed insulin formulations are preferred when available to minimize preparation errors.
Pharmacology · medium
A nurse is preparing to administer the morning dose of digoxin to a patient with heart failure. The patient reports feeling nauseated and anorexic since yesterday and mentions seeing 'yellow halos' around lights. The nurse notes a heart rate of 58 beats/min. Which action should the nurse take first?
AAdminister the digoxin and document the patient's symptoms.
BCheck the patient's serum digoxin level before administering the dose.
CWithhold the digoxin and notify the prescriber.
DAdminister an antiemetic and reassess the patient in 30 minutes.
Show the answer and why the others fail
Answer: C. Withhold the digoxin and notify the prescriber.
A
Administering digoxin when the patient is exhibiting signs of toxicity (anorexia, nausea, visual disturbances, bradycardia) could worsen toxicity and lead to life-threatening dysrhythmias. The medication should be withheld.
B
While checking the serum digoxin level is important, it is not the immediate priority. The nurse should first hold the dose and notify the prescriber, who will then order the appropriate laboratory tests. Administering the dose while awaiting results could be harmful.
C — correct
The patient is showing classic early signs of digoxin toxicity (gastrointestinal symptoms, visual halos, bradycardia). The priority nursing action is to hold the medication and promptly notify the prescriber for further evaluation and orders, such as checking a serum digoxin level.
D
Treating the nausea symptomatically without addressing the potential digoxin toxicity delays appropriate intervention and may allow the toxicity to progress to more serious dysrhythmias.
TakeawayEarly signs of digoxin toxicity include gastrointestinal symptoms (anorexia, nausea, vomiting) and visual disturbances (yellow-green halos). The nurse should withhold the drug and notify the prescriber immediately.
Pharmacology · medium
A patient is receiving intravenous gentamicin for a severe infection. The medication is infused over 30 minutes. The nurse is scheduled to draw a peak serum gentamicin level. At what time should the nurse obtain the blood sample?
A1 hour before the next dose is due
BImmediately before the next dose
C30 minutes after the infusion ends
D30 minutes after starting the infusion
Show the answer and why the others fail
Answer: C. 30 minutes after the infusion ends
A
This timing is not standard for peak or trough monitoring; it would yield a level that is neither a true peak nor a true trough, making interpretation unreliable.
B
This is the correct timing for a trough level, not a peak level. Trough levels are drawn just before the next dose to ensure the drug is clearing adequately and to minimize toxicity.
C — correct
For intravenous aminoglycosides, the peak serum level is drawn 30 minutes after the infusion ends to allow adequate drug distribution and obtain an accurate peak concentration.
D
This time point coincides with the end of the infusion. Drawing the sample immediately at the end of the infusion does not allow for drug distribution, which can result in a falsely elevated peak level. The sample should be drawn after the distribution phase is complete.
TakeawayFor intravenous aminoglycosides, the peak level is drawn 30 minutes after the infusion ends to assess therapeutic concentration; the trough level is drawn immediately before the next dose to monitor for toxicity.
Pharmacology · easy
A nurse is preparing to administer a new transdermal nitroglycerin patch to a client with stable angina. The nurse notes that the previous patch is still in place on the client's upper right chest. Which of the following actions should the nurse take?
ARemove the old patch and apply the new patch to the same site.
BRemove the old patch and hold the new patch until the prescriber is notified.
CRemove the old patch, clean the skin, and apply the new patch to a different site.
DApply the new patch to the left chest without removing the old patch.
Show the answer and why the others fail
Answer: C. Remove the old patch, clean the skin, and apply the new patch to a different site.
A
Applying a new patch to the same site can cause skin irritation, breakdown, and erratic drug absorption due to residual medication or adhesive.
B
There is no clinical reason to withhold the next scheduled dose; the nurse should simply apply the patch correctly and document the incident.
C — correct
The old patch must be removed to prevent overdose. Cleaning the skin removes residual medication, and rotating sites prevents local skin irritation and ensures consistent absorption.
D
Leaving the old patch in place would result in the client receiving a double dose of nitroglycerin, increasing the risk of severe hypotension and headache.
TakeawayAlways remove the old transdermal patch, clean the skin, and rotate application sites to prevent drug overdose and local skin reactions.
Pharmacology · medium
A nurse is providing discharge teaching to a patient with chronic stable angina who has been prescribed a transdermal nitroglycerin patch. Which statement by the patient indicates a correct understanding of the teaching?
A"I will wear the patch continuously and replace it every 24 hours."
B"I will remove the patch for 10 to 12 hours each day, usually at night."
C"I will cut the patch in half if I develop a headache."
D"I will apply the patch only when I feel chest pain."
Show the answer and why the others fail
Answer: B. "I will remove the patch for 10 to 12 hours each day, usually at night."
A
Continuous wear of nitroglycerin patches leads to tolerance, reducing the drug's effectiveness. A daily nitrate-free interval is required.
B — correct
A daily nitrate-free interval of 10–12 hours, typically at night, is necessary to prevent tolerance to transdermal nitroglycerin.
C
Cutting the patch alters the drug delivery system, causing unpredictable absorption and potential overdose. Headache is a common side effect that often subsides with continued use.
D
The transdermal patch is used for long-term prevention of angina, not for acute relief. Sublingual nitroglycerin is used for acute chest pain.
TakeawayTo prevent tolerance, transdermal nitroglycerin patches should be removed for 10–12 hours daily, typically at night, providing a nitrate-free interval.
Pharmacology · easy
A nurse is preparing to apply a nitroglycerin transdermal patch to a patient with chronic stable angina. Which action should the nurse take?
AShave the application site with a razor to remove hair before placing the patch.
BMassage the patch gently after application to promote adherence and enhance absorption.
CWear clean gloves while handling the patch to avoid self-absorption of the medication.
DApply the new patch to the same site as the previous one to maintain consistent absorption.
Show the answer and why the others fail
Answer: C. Wear clean gloves while handling the patch to avoid self-absorption of the medication.
A
Shaving can cause microabrasions that alter drug absorption and increase skin irritation; if hair removal is necessary, clipping is the preferred method.
B
Massaging the patch can accelerate drug release and absorption, leading to unpredictable therapeutic effects and an increased risk of adverse reactions such as hypotension.
C — correct
Nitroglycerin can be absorbed through the skin, so the nurse should wear gloves to prevent self-absorption and potential side effects such as headache or hypotension.
D
Rotating application sites prevents skin irritation and contact dermatitis, which can unpredictably alter drug absorption; using the same site increases the risk of local reactions.
TakeawayWhen applying a nitroglycerin transdermal patch, wear gloves to prevent self-absorption, rotate sites to avoid skin irritation, and never massage the patch.