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Pharmacology & Parenteral Therapies Practice Test

The most calculation-heavy and drug-knowledge-intensive category on the NCLEX-RN. These 25 questions cover medication administration, pharmacokinetics, drug classes, parenteral therapy, and IV calculations — with instant scoring and full rationales.

12–18%
Second largest category of the NCLEX-RN exam
25 questions ~15 minutes Instant scoring No signup needed

Pharmacology & Parenteral Therapies Quiz

Test your knowledge of Pharmacology & Parenteral Therapies with this NCLEX-RN practice quiz. This set of questions focuses on medication administration, IV therapies, dosage calculations, side effects, and safe nursing interventions.

25 questions | 90 minutes | 70% to pass

Question 1: A nurse administers a medication that has a high first-pass effect. The nurse understands that this means the drug:

  1. Will bypass the liver entirely and enter systemic circulation unchanged
  2. Will be excreted unchanged by the kidneys without any hepatic processing
  3. Will be significantly metabolized by the liver before reaching systemic circulation, reducing its bioavailability
  4. Will have an extended half-life due to slow hepatic metabolism

Answer: C — The first-pass effect means the liver extensively metabolizes the drug before it reaches systemic circulation, reducing bioavailability. This is why drugs like nitroglycerin are given sublingually - to bypass the liver and deliver more active drug to the bloodstream.

Question 2: A patient is receiving a medication with a narrow therapeutic index. The nurse should prioritize:

  1. Monitoring serum drug levels closely because the difference between a therapeutic and toxic dose is small
  2. Giving the medication only when the patient reports symptoms
  3. Administering the drug at the same time every day without monitoring blood levels
  4. Doubling the dose if the patient misses a scheduled administration

Answer: A — Narrow therapeutic index means the effective dose and toxic dose are very close together. Small changes in blood levels can cause toxicity or treatment failure. Examples: warfarin, digoxin, lithium, phenytoin. Close monitoring of serum levels is essential.

Question 3: A nurse is reviewing a medication order and notes the drug has a half-life of 6 hours. If the patient receives a single dose at 0800, approximately what percentage of the drug remains in the body at 2000?

  1. 25 percent - two half-lives have passed so 75 percent has been eliminated
  2. 100 percent - the drug has not been eliminated yet
  3. 50 percent - only one half-life has passed
  4. 75 percent - only one-quarter has been eliminated

Answer: A — 0800 to 2000 is 12 hours, which equals two half-lives (12 divided by 6). After one half-life: 50 percent remains. After two half-lives: 25 percent remains. Each half-life eliminates half of what is left.

Question 4: A patient is started on a new medication. The nurse explains that it will take several days to reach a steady-state concentration. The patient asks what this means. The BEST explanation is:

  1. The drug will stop working after several days and a new medication will be needed
  2. The drug has reached its maximum possible effect and no further doses are needed
  3. Steady state occurs when the amount of drug being administered equals the amount being eliminated, resulting in a consistent blood level
  4. The drug has completely left the body and needs to be restarted

Answer: C — Steady state is when drug intake equals drug elimination, producing consistent blood levels. It takes about 4 to 5 half-lives of regular dosing to achieve. Serum drug levels should be drawn after steady state is reached for accurate results.

Question 5: A patient is prescribed lisinopril (an ACE inhibitor) for hypertension. The nurse should monitor for which common adverse effect?

  1. Bradycardia and bronchospasm
  2. Hyperkalemia and persistent dry cough
  3. Hyperglycemia and weight gain
  4. Hypokalemia and muscle cramps

Answer: B — ACE inhibitors (-pril drugs) cause two signature side effects: hyperkalemia (reduced aldosterone means less potassium excretion) and a persistent dry cough (from bradykinin accumulation). Also monitor for first-dose hypotension and angioedema.

Question 6: A patient on warfarin (Coumadin) has an INR of 4.8. The nurse should FIRST:

  1. Encourage the patient to eat foods high in vitamin K to counteract the effect
  2. Hold the warfarin dose, notify the provider, and assess the patient for signs of bleeding
  3. Double the next dose to bring the INR back into therapeutic range
  4. Administer the next scheduled dose of warfarin as ordered

Answer: B — Therapeutic INR for warfarin is 2.0 to 3.0. An INR of 4.8 is dangerously elevated, indicating high bleeding risk. Hold the dose, notify the provider, and assess for bleeding signs: bruising, blood in urine or stool, gum bleeding, and headache.

Question 7: A patient is prescribed furosemide (Lasix), a loop diuretic. Which electrolyte imbalance should the nurse monitor for MOST closely?

  1. Hypernatremia and hyperkalemia
  2. Hypercalcemia and hyperphosphatemia
  3. Hyperkalemia and metabolic acidosis
  4. Hypokalemia and hypomagnesemia

Answer: D — Loop diuretics cause significant potassium and magnesium loss in urine. Hypokalemia is the most dangerous concern because it can cause fatal cardiac arrhythmias. Monitor potassium levels, assess for muscle weakness, and ensure potassium supplements are taken as prescribed.

Question 8: A nurse is caring for a patient prescribed both digoxin and furosemide. The nurse should be MOST concerned about which potential interaction?

  1. Digoxin will block the diuretic effect of furosemide
  2. Furosemide will increase digoxin absorption leading to subtherapeutic levels
  3. The two medications will chemically react if given at the same time
  4. Furosemide-induced hypokalemia increases the risk of digoxin toxicity

Answer: D — Furosemide causes potassium loss. Low potassium allows more digoxin to bind to cardiac cells, increasing toxicity risk even at normal digoxin levels. Monitor potassium closely (normal 3.5 to 5.0 mEq/L) and watch for digoxin toxicity signs.

Question 9: A nurse is educating a patient newly prescribed metformin (Glucophage) for type 2 diabetes. Which statement by the patient indicates a need for FURTHER teaching?

  1. I can drink alcohol freely because metformin does not interact with alcohol.
  2. I need to stop this medication before any procedure involving contrast dye.
  3. I should take this medication with meals to reduce stomach upset.
  4. I should report any unusual muscle pain or difficulty breathing to my doctor.

Answer: A — Alcohol plus metformin significantly increases the risk of lactic acidosis, a rare but potentially fatal complication. Patients must limit alcohol intake. The other statements are correct: take with food, hold before contrast dye procedures, and report muscle pain or breathing difficulty immediately.

Question 10: A patient is receiving IV vancomycin for a MRSA infection. Which assessment finding should the nurse report to the provider IMMEDIATELY?

  1. The patient requests a meal tray after the infusion is completed
  2. The patient develops facial flushing, hypotension, and a red rash on the upper body during rapid infusion
  3. The patient IV site is slightly tender without redness or swelling
  4. The patient reports mild nausea after the infusion

Answer: B — This describes Red Man Syndrome - a histamine reaction caused by infusing vancomycin too rapidly. Stop or slow the infusion, notify the provider, and administer antihistamines as ordered. Prevention: always infuse vancomycin over at least 60 minutes.

Question 11: A patient with bipolar disorder has a serum lithium level of 2.1 mEq/L. The nurse should:

  1. Administer the next dose as scheduled since this level is within therapeutic range
  2. Encourage the patient to increase fluid intake and administer the next dose
  3. Recognize this as a toxic level, hold the medication, notify the provider, and assess for toxicity symptoms
  4. Increase the dose because the level needs to be higher for bipolar maintenance

Answer: C — Therapeutic lithium level is 0.6 to 1.2 mEq/L. A level of 2.1 is toxic. Hold the medication and notify the provider. Toxicity signs: coarse tremors, vomiting, diarrhea, confusion, ataxia. Dehydration and sodium depletion worsen toxicity.

Question 12: A patient on digoxin reports seeing yellow-green halos around lights and has a heart rate of 52 bpm. The nurse should:

  1. Administer the digoxin because the heart rate is still above 50
  2. Hold the digoxin, check the serum digoxin level, and notify the provider immediately
  3. Encourage the patient to rest and recheck the heart rate in 4 hours
  4. Give an additional dose to address the visual disturbances

Answer: B — Yellow-green halos and bradycardia (below 60 bpm) are classic digoxin toxicity signs. Therapeutic level is 0.5 to 2.0 ng/mL. Always check apical pulse for 60 seconds before giving digoxin - hold and notify the provider if HR is below 60.

Question 13: A nurse is caring for a patient receiving morphine sulfate IV for post-surgical pain. Which finding requires IMMEDIATE intervention?

  1. Respiratory rate of 8 breaths per minute and patient is difficult to arouse
  2. Patient reports mild itching at the IV site
  3. Patient is resting quietly with eyes closed
  4. Pain level decreased from 8 out of 10 to 3 out of 10 after administration

Answer: A — Respiratory rate below 12 with excessive sedation indicates opioid-induced respiratory depression - the most dangerous opioid side effect. Stop the infusion, stimulate the patient, and prepare naloxone (Narcan), the opioid reversal agent. Monitor closely as naloxone wears off faster than most opioids.

Question 14: A patient with a history of seizures is receiving phenytoin (Dilantin). The nurse should monitor the serum drug level and intervene if it exceeds:

  1. 5 mcg/mL
  2. 10 mcg/mL
  3. 20 mcg/mL
  4. 50 mcg/mL

Answer: C — Therapeutic phenytoin level is 10 to 20 mcg/mL. Above 20 is toxic, causing nystagmus, ataxia, slurred speech, and confusion. Phenytoin has a narrow therapeutic index and nonlinear kinetics, meaning small dose changes can cause large level increases.

Question 15: Before administering any medication, the nurse must verify the Five Rights. These include right patient, right drug, right dose, right route, and:

  1. Right pharmacy
  2. Right insurance
  3. Right diagnosis
  4. Right time

Answer: D — The Five Rights are: Right Patient (two identifiers), Right Drug, Right Dose, Right Route, and Right Time. This is the fundamental safety check before every medication administration. Many facilities add Right Documentation and Right to Refuse.

Question 16: A nurse is preparing to administer an intramuscular (IM) injection to an adult. The PREFERRED site for a large-volume IM injection is the:

  1. Dorsogluteal muscle in the upper outer buttock
  2. Ventrogluteal muscle in the hip area
  3. Deltoid muscle of the upper arm
  4. Vastus lateralis muscle of the outer thigh

Answer: B — The ventrogluteal site is preferred for adult IM injections because it has the largest muscle mass and is free from major nerves and blood vessels. The dorsogluteal is no longer recommended due to sciatic nerve proximity. The deltoid is limited to 1 mL volumes.

Question 17: A nurse administers a medication to the wrong patient. The FIRST action the nurse should take is:

  1. Document the error in the patient chart and take no further action
  2. Immediately notify the patient family before telling anyone else
  3. Hide the error and hope no adverse effects occur
  4. Assess the patient for any adverse effects of the medication

Answer: D — Patient safety is always the first priority. Immediately assess for adverse effects from the wrong medication, then notify the provider and charge nurse, monitor the patient closely, and complete an incident report. Never conceal a medication error.

Question 18: A patient receiving heparin IV has a PTT result of 120 seconds (control: 25-35 seconds). The nurse should:

  1. Administer vitamin K to reverse the heparin effect
  2. Continue the heparin infusion at the current rate since anticoagulation is the goal
  3. Stop the heparin infusion immediately, notify the provider, and have protamine sulfate available
  4. Increase the infusion rate to achieve even greater anticoagulation

Answer: C — Therapeutic PTT for heparin is 1.5 to 2.5 times control (approximately 46 to 70 seconds). A PTT of 120 is dangerously high with serious bleeding risk. Stop heparin and prepare protamine sulfate (heparin antidote). Note: vitamin K reverses warfarin, not heparin.

Question 19: A nurse is verifying insulin doses with another nurse before administration. The patient is prescribed 8 units of insulin lispro (Humalog) before lunch. The nurse should administer this insulin:

  1. At bedtime regardless of when the meal is eaten
  2. 2 hours after the meal to prevent postprandial hypoglycemia
  3. Within 15 minutes before the meal because rapid-acting insulin works quickly
  4. 30 to 60 minutes before the meal to allow adequate onset time

Answer: C — Insulin lispro (Humalog) is rapid-acting with onset in 15 minutes, peak at 1 to 2 hours, and duration of 3 to 4 hours. Give within 15 minutes before meals. The 30 to 60 minute timing applies to regular (short-acting) insulin, not rapid-acting.

Question 20: A patient is receiving IV potassium chloride (KCl) 40 mEq in 1000 mL normal saline. The nurse should ensure that:

  1. The KCl is given undiluted directly into a peripheral vein
  2. The entire 1000 mL infusion is completed within 1 hour
  3. The KCl is administered as a rapid IV push over 5 minutes
  4. The infusion is administered via an infusion pump and the rate does not exceed 10 mEq per hour in most circumstances

Answer: D — IV potassium is a high-alert medication. NEVER give IV push - rapid potassium administration causes fatal cardiac arrest. Always dilute, use an infusion pump, and limit to 10 mEq/hour for peripheral lines. Monitor the IV site, cardiac rhythm, and potassium levels.

Question 21: A physician orders 1000 mL of 0.9 percent normal saline to infuse over 8 hours. The IV tubing drop factor is 15 gtt/mL. What is the correct drip rate in drops per minute (gtt/min)?

  1. 31 gtt/min
  2. 42 gtt/min
  3. 21 gtt/min
  4. 63 gtt/min

Answer: A — Formula: (Volume x Drop factor) divided by (Time in minutes). Calculation: (1000 x 15) divided by (480 minutes) = 15000 divided by 480 = 31.25, rounded to 31 gtt/min. Always convert hours to minutes first.

Question 22: A nurse is caring for a patient with a peripherally inserted central catheter (PICC line). Which assessment finding requires IMMEDIATE action?

  1. The external catheter length measures the same as at insertion
  2. The patient reports no pain at the insertion site
  3. The PICC dressing is clean, dry, and intact
  4. The patient arm on the PICC side is swollen, red, and warm compared to the other arm

Answer: D — Unilateral arm swelling, redness, and warmth on the PICC side indicates a deep vein thrombosis (DVT). Notify the provider immediately. The clot can embolize to the lungs causing pulmonary embolism. Expect orders for ultrasound and possible anticoagulation.

Question 23: A patient receiving total parenteral nutrition (TPN) through a central line develops sudden onset of tachycardia, hypotension, and respiratory distress immediately after a central line dressing change. The nurse should suspect:

  1. Fluid volume overload from the TPN infusion rate
  2. An allergic reaction to the dressing adhesive
  3. Air embolism from entry of air into the central venous catheter
  4. Hyperglycemia from the high dextrose concentration in TPN

Answer: C — Sudden cardiovascular collapse after a central line dressing change suggests air embolism. Immediately clamp the catheter, position the patient in left lateral Trendelenburg (left side down, head low), administer oxygen, and notify the provider.

Question 24: A nurse is infusing a medication through a peripheral IV and notices the surrounding tissue is swollen, cool, and pale with the patient reporting burning pain at the site. This indicates:

  1. An allergic reaction to the IV solution requiring epinephrine
  2. Infiltration requiring immediate discontinuation of the IV and removal of the catheter
  3. Phlebitis requiring warm compress application
  4. A normal response to IV fluid administration

Answer: B — Swelling, coolness, pallor, and burning at the IV site are classic infiltration signs - fluid is leaking into surrounding tissue. Stop the infusion immediately, remove the catheter, elevate the extremity, and apply appropriate compresses. Restart the IV at a new site.

Question 25: A patient is prescribed vancomycin 1 g IV every 12 hours. The pharmacy sends vancomycin 1 g in 250 mL normal saline. Per protocol, the infusion must run over a minimum of 60 minutes. The nurse should set the IV pump to:

  1. 250 mL per hour
  2. 500 mL per hour
  3. 125 mL per hour
  4. 100 mL per hour

Answer: A — 250 mL divided by 1 hour equals 250 mL/hour. IV pumps are set in mL/hour. Infusing vancomycin faster than 60 minutes increases the risk of Red Man Syndrome. Always verify the minimum infusion time for each medication.

What your score means

85% or above — Exam ready on pharmacology

Strong performance on one of the most drug-knowledge-intensive sections of the NCLEX-RN. You understand key drug classes, monitoring parameters, and the five rights at an exam-ready level. Review any missed questions and move on.

70–84% — Close, but sharpen your drug class knowledge.

You’re likely losing points on high-alert medications, antidote associations, or IV calculation questions. Focus your review on the drug class reference table and high-alert strips below, then retake.

Below 70% — This needs targeted study.

Pharmacology is 12–18% of the exam and the questions are scenario-heavy. Work through every cheat sheet section below, especially the drug class table and high-alert medications, then revisit our NCLEX-RN Study Guide pharmacology chapter before retaking.

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What’s covered in Pharmacology & Parenteral

This category tests your ability to safely administer medications, identify adverse effects, anticipate antidotes, calculate IV rates, and recognize which drug interactions require nursing action. Questions are almost always scenario-based — you’ll be given a patient situation and asked what to do next.

Pharmacokinetics & Pharmacodynamics

Absorption, distribution, metabolism, elimination. Drug half-life, onset/peak/duration, therapeutic index, and first-pass effect.

~4 questions

Drug Classes & Mechanisms

Antihypertensives, anticoagulants, diuretics, antibiotics, antidiabetics, analgesics, antipsychotics — expected effects, adverse effects, and contraindications.

~7 questions

High-Alert Medications

Anticoagulants, insulin, digoxin, lithium, opioids — narrow therapeutic index drugs, toxicity signs, and antidotes the RN must know immediately.

~5 questions

Medication Administration & Five Rights

Right patient, drug, dose, route, time. Nurse’s responsibilities before, during, and after administration, including patient education and documentation.

~4 questions

IV Therapy & Calculations

IV flow rate calculations, drip rates, fluid compatibility, central vs. peripheral access, PICC line care, TPN nursing responsibilities.

~5 questions

All NCLEX-RN practice topics

Scored well here? Keep the momentum going. Each topic has 25 focused questions with full rationales.

Safe & Effective Care
25 questions — 21–33%
You are here
Pharmacology & Parenteral
25 questions — 12–18%
Physiological Adaptation
25 questions — 11–17%
Reduction of Risk Potential
25 questions — 9–15%
Health Promotion & Maintenance
25 questions — 6–12%
Psychosocial Integrity
25 questions — 6–12%
Mental Health Nursing
25 questions
Maternal & Newborn
25 questions
Pediatric Nursing
25 questions
Lab Values & Diagnostics
25 questions
Full 75-Question Test
All categories · Exam conditions

How to master Pharmacology & Parenteral

Learn drug classes by grouping, not individual drugs

There are thousands of drugs but only a few dozen classes. If you know what all ACE inhibitors do, you can answer a question about ramipril, lisinopril, or enalapril without ever having memorized that specific drug. Study mechanism, expected effect, common adverse effects, and contraindications — these apply to every drug in the class. The NCLEX-RN almost never tests a drug by generic name alone without context.

Memorise antidotes for narrow-therapeutic-index drugs cold

The NCLEX loves to test toxicity scenarios: a patient is on warfarin and has a supratherapeutic INR — what do you give? Know the antidote pairs: heparin → protamine sulfate, warfarin → vitamin K, digoxin → digoxin immune Fab, opioids → naloxone (Narcan), benzodiazepines → flumazenil, acetaminophen → N-acetylcysteine. These appear in every pharmacology set.

Know the five rights — and the nursing implications behind each

The five rights aren’t just a checklist — each one has a nursing action embedded in it. Right patient means two identifiers. Right drug means verifying allergies. Right dose means knowing the normal range and calculating if needed. Right route means understanding why the route matters (e.g., IM vs. IV onset times). Right time means knowing peak times and when to hold (e.g., hold digoxin if HR <60).

Practice IV calculations until they’re automatic

Flow rate questions appear consistently: mL/hr, drops/min, and infusion time calculations. The formula is always Dose ordered ÷ Dose available × Vehicle = Amount to give. For drip rates: (Volume ÷ Time) × Drop factor = gtt/min. Work through at least 20 calculations before your exam so you’re not doing this under pressure for the first time.

Retake until you score 85%+ consistently

Pharmacology is 12–18% of your exam. But unlike some categories, wrong answers here often indicate a specific knowledge gap (not just strategy) — so use each wrong answer to identify exactly which drug class or concept to revisit. One targeted study session per failed question gets you there faster than re-reading entire chapters.

Quick Reference Cheat Sheets

Everything you need to know cold for pharmacology questions — the five rights pipeline, a drug class reference table, high-alert medication strips, and IV therapy quick-reference.

The Five Rights of Medication Administration
Each right carries a nursing action — know what to verify and what to do when something doesn’t check out.
1
Right Patient
Use 2 identifiers — name + DOB or MRN. Never room number alone.
Check armband
2
Right Drug
Verify allergy history. Check generic vs. brand. Confirm with MAR.
Verify allergies
3
Right Dose
Know normal dosage range. Calculate carefully. Question doses outside range.
Calculate & verify
4
Right Route
PO, IV, IM, SubQ, sublingual — route changes onset, duration, and bioavailability.
Match the order
5
Right Time
Know peak times. Hold parameters (e.g., digoxin HR <60, hold and notify).
Know hold rules
High-Yield Drug Class Reference
Most frequently tested classes on the NCLEX-RN
Drug Class Key Examples Primary Use Critical Adverse Effect Nurse Action / Note
ACE Inhibitors lisinopril, enalapril, captopril HTN, heart failure, post-MI Dry cough, angioedema, hyperkalemia Monitor K⁺ Hold if angioedema occurs — stop permanently
Beta-Blockers metoprolol, atenolol, carvedilol HTN, angina, dysrhythmias, heart failure Bradycardia, hypotension, bronchospasm Hold if HR <60 Never stop abruptly — taper always
Anticoagulants heparin, warfarin, enoxaparin DVT, PE, atrial fibrillation, post-MI Hemorrhage, HIT (heparin) Heparin → protamine Warfarin → Vit K Monitor PTT (heparin), INR (warfarin)
Diuretics (Loop) furosemide, bumetanide Edema, heart failure, HTN Hypokalemia, ototoxicity (IV push rapid) Monitor K⁺ Administer IV furosemide ≤4 mg/min
Diuretics (K-sparing) spironolactone HTN, heart failure, hyperaldosteronism Hyperkalemia, gynecomastia Avoid K⁺ suppl. Do not combine with ACE inhibitors without close monitoring
Insulin Regular, NPH, glargine, lispro Type 1 & 2 DM, DKA, hyperkalemia Hypoglycemia, hypokalemia Hypoglycemia → glucagon / D50W Only Regular insulin given IV
Digoxin digoxin (Lanoxin) Heart failure, atrial fibrillation Toxicity: nausea, visual changes (yellow-green halos), bradycardia Hold if HR <60 Toxicity → Digibind (Digoxin immune Fab) Therapeutic level: 0.5–2 ng/mL
Opioid Analgesics morphine, oxycodone, fentanyl Moderate-severe pain Respiratory depression, constipation, sedation Resp. depression → Naloxone (Narcan) Assess RR before each dose
Antipsychotics (Typical) haloperidol, chlorpromazine Schizophrenia, acute agitation EPS (dystonia, akathisia), tardive dyskinesia, NMS EPS → Benztropine (Cogentin) Monitor for NMS: hyperthermia, rigidity, altered LOC
Lithium lithium carbonate Bipolar disorder (mood stabilizer) Toxicity: tremor, diarrhea, confusion, seizures Therapeutic: 0.6–1.2 mEq/L Maintain adequate sodium and fluid intake
Benzodiazepines lorazepam, diazepam, midazolam Anxiety, seizures, alcohol withdrawal, sedation Respiratory depression, sedation, dependence Overdose → Flumazenil (Romazicon) Fall risk — raise bed rails
Corticosteroids prednisone, methylprednisolone, dexamethasone Inflammation, autoimmune disorders, adrenal insufficiency Hyperglycemia, immunosuppression, osteoporosis, Cushing’s Monitor BG Never stop abruptly — taper dose. Give with food.
High-Alert Medications — Toxicity at a Glance
These drugs have narrow therapeutic indexes. Know the toxicity signs, labs to monitor, and antidotes for each — they appear on nearly every NCLEX-RN pharmacology set.
Digoxin
Cardiac glycoside
Toxicity Signs
Nausea/vomiting, yellow-green halos, bradycardia, dysrhythmias, fatigue
Monitor
Serum digoxin level (0.5–2 ng/mL), K⁺ (hypokalemia ↑ toxicity risk), HR before each dose
Antidote
Digoxin immune Fab (Digibind) — hold drug, notify provider, prepare antidote
Lithium
Mood stabilizer
Toxicity Signs
Fine tremor (early) → coarse tremor, diarrhea, confusion, ataxia, seizures (late)
Monitor
Serum level (therapeutic: 0.6–1.2 mEq/L). Adequate Na⁺/fluid intake — dehydration ↑ lithium level
Antidote
No specific antidote — hold drug, increase fluid/sodium, hemodialysis for severe toxicity
Warfarin
Anticoagulant
Toxicity Signs
Bleeding gums, hematuria, black/tarry stools, prolonged bleeding from cuts, INR >3.0
Monitor
INR (therapeutic: 2.0–3.0) for A-fib/DVT. PT. Teach patient to avoid NSAIDs, consistent vitamin K intake
Antidote
Vitamin K (phytonadione) for elevated INR. Fresh frozen plasma for active hemorrhage
Insulin
Antidiabetic
Toxicity Signs
Hypoglycemia: diaphoresis, tremor, tachycardia, confusion, seizures if BG <70 mg/dL
Monitor
Blood glucose before each dose. Know onset/peak/duration for each insulin type. Only Regular insulin is given IV
Antidote
Conscious: 15g fast-acting carbs (15/15 rule). Unconscious: D50W IV or glucagon IM/SubQ
Heparin
Anticoagulant
Toxicity Signs
Hemorrhage, HIT (platelet drop >50% on days 5–10), hematoma at injection site
Monitor
aPTT (therapeutic: 60–100 sec) or 1.5–2.5× normal. Platelet count for HIT. Injection sites
Antidote
Protamine sulfate — 1 mg per 100 units heparin. If HIT: stop heparin immediately, use alternative anticoagulant
IV Therapy & Calculations Quick Reference
The formulas and nursing rules that appear most often in NCLEX-RN pharmacology questions.
IV Calculation Formulas
Flow rate (mL/hr): Total volume (mL) ÷ Time (hr)
Drip rate (gtt/min): (Volume mL ÷ Time min) × Drop factor
Dose calculation: (Ordered dose ÷ Available dose) × Vehicle
Weight-based dose: Dose (mg/kg) × Weight (kg) = Total dose
Infusion time: Total volume (mL) ÷ Rate (mL/hr) = Hours
IV Nursing Rules
Change IV tubing every 72–96 hours per facility policy (lipid tubing every 24 hrs)
Assess IV site for infiltration (cool/pale/swelling) and phlebitis (red/warm/hard)
If IV is behind schedule: do not speed up rate to catch up without a provider order
TPN: dedicated line, monitor BG q4–6h, never hang for >24 hours per bag
Blood products: verify with 2 nurses at bedside, infuse within 4 hours, use only NS
Full test
Take the Full 75-Question NCLEX-RN Practice Test
All client needs categories. Exam conditions. Instant results with full score breakdown.

Frequently asked questions

How much of the NCLEX-RN is pharmacology?
Pharmacology & Parenteral Therapies accounts for 12–18% of the NCLEX-RN, making it the second largest category after Safe & Effective Care. With a minimum 75-question exam, you can expect roughly 9–14 pharmacology questions on your actual test.
What drug classes are most commonly tested?
The most frequently tested classes are anticoagulants (heparin, warfarin), cardiac medications (digoxin, beta-blockers, ACE inhibitors), insulin, opioid analgesics, antipsychotics (especially EPS and NMS), lithium, and diuretics. Focus on mechanism, adverse effects, antidotes, and nursing monitoring parameters for each class rather than memorizing individual drugs.
Do I need to memorise drug calculations?
Yes. The NCLEX-RN includes fill-in-the-blank calculation questions where you must enter the exact numeric answer. You’ll need to calculate IV flow rates, drip rates, weight-based doses, and mg-to-mL conversions. Practice the three core formulas (flow rate, drip rate, dose calculation) until you can apply them quickly without a formula sheet.
What’s the difference between pharmacokinetics and pharmacodynamics?
Pharmacokinetics describes what the body does to the drug: absorption, distribution, metabolism, and elimination (ADME). Pharmacodynamics describes what the drug does to the body: its mechanism of action and the relationship between drug concentration and effect. The NCLEX tests pharmacokinetics mostly through clinical implications — for example, why a drug with a long half-life accumulates in renal failure patients.
What are the most important antidote pairs to know?
The six antidote pairs that appear most consistently are: Heparin → Protamine sulfate; Warfarin → Vitamin K; Digoxin toxicity → Digoxin immune Fab (Digibind); Opioid overdose → Naloxone (Narcan); Benzodiazepine overdose → Flumazenil (Romazicon); Acetaminophen overdose → N-acetylcysteine (Mucomyst).
Can I take this quiz more than once?
Yes, unlimited retakes with no signup required. For pharmacology specifically, we recommend retaking after each study session focused on the drug classes where you lost points. Because this category has high fact density, spaced repetition — reviewing wrong answers 2–3 days later — is particularly effective.

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