Pharmacokinetics and pharmacodynamics
A nurse is explaining drug absorption to a patient. Which factor is most likely to increase the rate of drug absorption?
A. Enteric coating
B. Slow gastric emptying
C. High blood flow to the absorption site
D. Low drug solubility
Correct answer: C. High blood flow to the absorption site
Rationale: Increased blood flow enhances absorption by carrying the drug away from the site.
The breakdown of oral drugs and forming them into small particles?
What is disintegration?
A nurse is administering an oral medication to a patient. Which factor is most likely to reduce the drug’s bioavailability?
A. Taking the drug with a full glass of water
B. Administering the drug on an empty stomach
C. Extensive first-pass metabolism in the liver
D. Rapid dissolution of the drug in the stomach
Correct answer: C. Extensive first-pass metabolism in the liver
Rationale: The first-pass effect significantly reduces the amount of active drug reaching systemic circulation
A nurse is preparing to administer furosemide (Lasix). Which lab value should the nurse be most concerned about before giving the medication?
A. Hemoglobin 13.5 g/dL
B. Sodium 138 mEq/L
C. Potassium 2.9 mEq/L
D. Glucose 110 mg/dL
Correct answer: C. Potassium 2.9 mEq/L
Rationale: Furosemide can cause further potassium loss; 2.9 is below normal and puts the patient at risk for arrhythmias.
This activates receptors.
What is an agonist?
A nurse is teaching a client about a newly prescribed medication. Why is it important for the nurse to understand pharmacokinetics?
A. To prescribe the correct medication
B. To administer the drug faster
C. To explain how the drug works in the body
D. To reduce the cost of treatment
Correct answer: C. To explain how the drug works in the body
Rationale: Understanding pharmacokinetics allows the nurse to educate the client on how the medication is absorbed, distributed, metabolized, and excreted.
Which pharmacokinetic phase is primarily responsible for the drug becoming available in the bloodstream after oral administration?
A. Distribution
B. Metabolism
C. Absorption
D. Excretion
Correct answer: C. Absorption
Rationale: Absorption is the process of a drug entering the bloodstream after administration.
The process involves combining small drug particles with liquid to form a solution.
What is dissolution?
A nurse is teaching a patient about sublingual nitroglycerin. Why is the sublingual route preferred in this case?
A. It slows absorption to prevent hypotension
B. It increases first-pass metabolism
C. It enhances bioavailability by bypassing the liver
D. It delays peak drug concentration
Correct answer: C. It enhances bioavailability by bypassing the liver.
Rationale: Sublingual administration avoids the hepatic first-pass effect and allows rapid absorption.
A nurse is preparing to administer warfarin (Coumadin). Which lab value is most important to check?
A. Platelets
B. INR
C. Hemoglobin
D. White blood cell count
Correct answer: B. INR
Rationale: INR assesses the effectiveness and safety of warfarin therapy. A high INR increases bleeding risk.
This prevents receptor activiation.
What is an antagonist?
A client expresses anxiety about starting a new medication. Which nursing action best supports a compassionate approach?
A. Provide the client with the medication information leaflet only
B. Instruct the client to call the pharmacy with any questions
C. Encourage the client to ask questions and offer clear explanations
D. Tell the client not to worry because the provider prescribed it
Correct answer: C. Encourage the client to ask questions and offer clear explanations
Rationale: Compassionate care includes creating a safe space for clients to ask questions and receive trustworthy information.
A drug with a high first-pass effect is most likely to be:
A. Excreted in the urine unchanged
B. Inactivated before reaching systemic circulation
C. Rapidly absorbed into the bloodstream
D. Slowly metabolized by the kidneys
Correct answer: B. Inactivated before reaching systemic circulation
Rationale: The first-pass effect refers to the metabolism of a drug in the liver before it reaches systemic circulation.
Drug movement from the GI tract to the bloodstream.
What is drug absorption?
Which form of a drug would likely have the lowest bioavailability?
A. Intravenous injection
B. Liquid oral solution
C. Enteric-coated tablet
D. Sublingual tablet
Correct answer: C. Enteric-coated tablet
Rationale: Enteric coatings delay absorption until the drug reaches the intestine, reducing bioavailability if not absorbed properly.
A patient is prescribed vancomycin IV. Which lab value is most critical to check before administration?
A. Creatinine
B. Hemoglobin
C. ALT
D. Potassium
Correct answer: A. Creatinine
Rationale: Vancomycin is nephrotoxic. Elevated creatinine suggests impaired kidney function and increased risk of toxicity.
When drugs bind to receptors to cause or block an action.
What is receptor theory?
A client tells the nurse they are considering stopping their medication due to side effects. What is the nurse’s best response?
A. "You should never stop a medication on your own."
B. "Let me notify the provider and we can explore options."
C. "If you stop, the condition will get worse."
D. "Many people take this without problems."
Correct answer: B. "Let me notify the provider and we can explore options."
Rationale: Nurses advocate for clients and support collaborative care, especially when medication adjustments are needed.
Which patient condition is most likely to affect drug metabolism?
A. Chronic kidney disease
B. Liver cirrhosis
C. Hypothyroidism
D. Hypertension
Correct answer: B. Liver cirrhosis
Rationale: The liver is the primary site of drug metabolism; liver dysfunction can impair this process.
The desirable response of a medication on the body.
What is primary effect?
A patient has delayed gastric emptying due to a gastrointestinal condition. How will this most likely affect drug bioavailability?
A. Increase due to enhanced gastric absorption
B. Decrease due to prolonged exposure to gastric acid
C. No effect on drug levels
D. Increase first-pass metabolism
Correct answer: B. Decrease due to prolonged exposure to gastric acid
Rationale: Delayed gastric emptying can degrade drugs in the stomach, reducing their absorption and bioavailability.
A nurse is giving digoxin to a patient. Which lab result should prompt the nurse to hold the medication and notify the provider?
A. Digoxin level 2.5 ng/mL
B. Sodium 140 mEq/L
C. Potassium 4.0 mEq/L
D. BUN 15 mg/dL
Correct answer: A. Digoxin level 2.5 ng/mL
Rationale: Therapeutic range for digoxin is 0.5–2.0 ng/mL. A level of 2.5 indicates toxicity.
And altered drug effect due to another drug in the patient's system.
What is a drug interaction?
A nurse notices that a client has missed multiple doses of their prescribed antibiotic. What is the nurse’s priority action?
A. Inform the provider of noncompliance
B. Educate the client on the importance of medication adherence
C. Record it in the nurse’s notes
D. Reinforce the prescription without discussing the issue
Correct answer: B. Educate the client on the importance of medication adherence
Rationale: Nurses play a vital role in helping clients understand the importance of sticking to medication schedules.
A nurse is reviewing a drug’s half-life. What does the half-life of a drug indicate?
A. Time it takes for the drug to be absorbed
B. Time it takes for the drug to be eliminated completely
C. Time it takes for the drug concentration to decrease by 50%
D. Time until the drug reaches peak effect
Correct answer: C. Time it takes for the drug concentration to decrease by 50%
Rationale: Half-life reflects how quickly a drug is eliminated from the body.
What is secondary effect?
Which route of drug administration typically provides the highest and most consistent bioavailability?
A. Oral
B. Rectal
C. Intravenous
D. Subcutaneous
Correct answer: C. Intravenous
Rationale: IV drugs have 100% bioavailability as they are delivered directly into the bloodstream.
A patient receiving heparin therapy has an aPTT of 95 seconds. What should the nurse do next?
A. Administer the dose as scheduled
B. Notify the provider immediately
C. Give protamine sulfate
D. Document and monitor vitals
Correct answer: B. Notify the provider immediately
Rationale: Therapeutic aPTT for heparin is generally 1.5–2.5 times normal (25–35 seconds); 95 is dangerously high.
A change occurring in absorption, distribution, metabolism and excretion.
During a follow-up visit, a client reports nausea after starting a new medication. Which nursing action demonstrates compassionate, client-centered care?
A. Encourage the client to take the medication with food if appropriate
B. Advise the client to stop taking the medication
C. Tell the client nausea is common and will pass
D. Instruct the client to ignore the side effects
Correct answer: A. Encourage the client to take the medication with food if appropriate
Rationale: Nurses help manage side effects and educate clients on how to take medications safely and comfortably.
A drug is highly protein-bound. Which condition may increase its free drug concentration in the blood?
A. Hyperlipidemia
B. Hypoalbuminemia
C. Hypernatremia
D. Hypertension
Correct answer: B. Hypoalbuminemia
Rationale: Low albumin levels reduce protein binding, increasing the amount of free (active) drug.
The study of the way drugs affect the body.
What is pharmacodynamics?
A nurse notes a patient is taking antacids along with an oral iron supplement. Which effect should the nurse expect on the iron's bioavailability?
A. Increased absorption due to higher pH
B. No change in absorption
C. Decreased absorption due to altered gastric pH
D. Faster absorption in the intestines
Correct answer: C. Decreased absorption due to altered gastric pH
Rationale: Antacids raise gastric pH, reducing the solubility and absorption of iron.
A patient is ordered acetaminophen for pain. Which lab value should the nurse assess to prevent toxicity?
A. AST/ALT
B. Creatinine
C. aPTT
D. Potassium
Correct answer: A. AST/ALT
Rationale: Acetaminophen is hepatotoxic in high doses; monitor liver enzymes.
The sum of the effects of two drugs.
What is an additive?
A nurse reviews lab results for a client on a new medication and notes subtherapeutic levels. What is the nurse’s best response?
A. Wait for the next scheduled dose
B. Notify the provider about possible dose adjustment
C. Continue the current regimen
D. Instruct the client to take double the next dose
Correct answer: B. Notify the provider about possible dose adjustment
Rationale: Monitoring therapeutic levels and advocating for medication changes are key nursing responsibilities.
A nurse understands that a drug administered intravenously differs from an oral drug because IV drugs:
A. Undergo first-pass metabolism
B. Have variable absorption
C. Have 100% bioavailability
D. Are less potent
Correct answer: C. Have 100% bioavailability
Rationale: IV drugs enter the bloodstream directly and completely, bypassing absorption and first-pass metabolism.
The time it takes for a drug to reach minimum effective concentration.
What is onset?
A nurse is teaching a patient about the effects of high-fat meals on certain oral medications. Which outcome is most likely?
A. Immediate peak drug levels
B. Decreased absorption and bioavailability
C. Increased absorption for lipophilic drugs
D. Elimination of the first-pass effect
Correct answer: C. Increased absorption for lipophilic drugs
Rationale: High-fat meals can enhance absorption of fat-soluble drugs, increasing bioavailability.
Before administering enalapril (an ACE inhibitor), which lab result should concern the nurse most?
A. Potassium 5.8 mEq/L
B. BUN 15 mg/dL
C. Sodium 138 mEq/L
D. Creatinine 0.9 mg/dL
Correct answer: A. Potassium 5.8 mEq/L
Rationale: ACE inhibitors can cause hyperkalemia, increasing the risk of cardiac arrhythmias.
This is the term for when the effect is much greater than the effect of either drug alone.
What is synergistic?
A client asks the nurse why they need to take a medication twice a day. Which is the nurse’s best response?
A. "That’s just how the pharmacy packaged it."
B. "I don’t know; you can ask the doctor."
C. "The dosing schedule keeps the medication at a safe and effective level."
D. "You can take both doses at once if that’s easier."
Correct answer: C. "The dosing schedule keeps the medication at a safe and effective level."
Rationale: Understanding pharmacodynamics helps nurses educate clients on why proper dosing schedules are necessary.
8. What is the primary organ responsible for drug excretion?
A. Liver
B. Pancreas
C. Kidney
D. Lungs
Correct answer: C. Kidney
Rationale: The kidneys are the major route for elimination of most drugs and their metabolites.
Highest concentration of medication in the blood.
A patient has liver cirrhosis. How might this condition affect the bioavailability of drugs that undergo first-pass metabolism?
A. It will decrease bioavailability
B. It will have no effect
C. It will increase bioavailability
D. It will delay drug excretion
Correct answer: C. It will increase bioavailability
Rationale: Impaired liver function reduces first-pass metabolism, allowing more drug to enter systemic circulation.
A patient is scheduled to receive lithium. Which lab value requires immediate action before administration?
A. Lithium level 1.6 mEq/L
B. Sodium 140 mEq/L
C. Creatinine 0.8 mg/dL
D. WBC count 5,000/mm³
Correct answer: A. Lithium level 1.6 mEq/L
Rationale: Therapeutic lithium range is 0.6–1.2 mEq/L. 1.6 is toxic and should be reported.
When one drug reduces or blocks effects of another drug.
What is antagonistic?
Why is it important for a nurse to be seen as a trustworthy source of medication information?
A. It increases client dependency on the nurse
B. It prevents clients from calling their providers
C. It builds trust and encourages client engagement in care
D. It allows the nurse to manage the medication plan independently
Correct answer: C. It builds trust and encourages client engagement in care
Rationale: Being a reliable source helps foster a collaborative and supportive nurse-client relationship.
A nurse notes that an older adult patient has decreased renal function. Which pharmacokinetic process is most likely to be affected?
A. Absorption
B. Distribution
C. Metabolism
D. Excretion
Correct answer: D. Excretion
Rationale: Aging decreases renal function, which can impair drug clearance and increase toxicity risk.
How long a drug exerts a therapeutic effect.
A nurse is administering a drug that is rapidly metabolized by the liver. Which route should the nurse avoid to maximize bioavailability?
A. Intramuscular
B. Sublingual
C. Oral
D. Intravenous
Correct answer: C. Oral
Rationale: Oral drugs are most affected by first-pass metabolism, reducing bioavailability for such drugs.
A nurse is preparing to administer metformin. Which lab result requires the nurse to hold the dose?
A. Creatinine 2.1 mg/dL
B. Potassium 3.8 mEq/L
C. Hemoglobin A1c 7.2%
D. ALT 35 U/L
Correct answer: A. Creatinine 2.1 mg/dL
Rationale: Metformin is contraindicated in renal impairment due to the risk of lactic acidosis.
What the drugs do to the body. For example, stimulation, depression, antimicrobial, etc.
What is mechanism of action?
A nurse is assessing a client for therapeutic and adverse reactions to a new medication. This action reflects an understanding of:
A. Medication administration timing
B. The pharmacokinetics of other drugs
C. Pharmacodynamics and monitoring drug effects
D. How to reduce costs of care
Correct answer: C. Pharmacodynamics and monitoring drug effects
Rationale: Pharmacodynamics refers to how the drug affects the body, including therapeutic and adverse responses.
A drug has a short half-life. What should the nurse expect regarding dosing frequency?
A. Once daily
B. Twice daily
C. Less frequent dosing
D. No regular dosing needed
Correct answer: B. Twice daily
Rationale: A short half-life means the drug is eliminated quickly, requiring more frequent dosing to maintain therapeutic levels.
Labs required in safe antibiotic therapeutic drug monitoring.
What are peak and trough?
A patient is prescribed two medications that are both metabolized by the same liver enzyme. What effect may this have on drug bioavailability?
A. No effect on drug levels
B. Increased bioavailability due to enzyme competition
C. Decreased absorption in the stomach
D. Enhanced first-pass metabolism
Correct answer: B. Increased bioavailability due to enzyme competition
Rationale: When two drugs compete for the same liver enzymes, metabolism slows down, increasing the availability of the active drug.
A patient is prescribed gentamicin IV. Which lab value should be monitored closely to prevent complications?
A. BUN and Creatinine
B. Platelet count
C. INR
D. Hemoglobin
Correct answer: A. BUN and Creatinine
Rationale: Gentamicin is nephrotoxic. Monitor kidney function during therapy.
A nurse is caring for a patient receiving IV vancomycin every 12 hours. The healthcare provider has ordered a trough level to be drawn. When should the nurse schedule the blood draw?
A. 15 minutes after the start of the infusion
B. 30 minutes after the end of the infusion
C. Immediately before the next dose
D. One hour after the peak effect is observed
Correct answer: C. Immediately before the next dose
Rationale: Trough levels are drawn just before the next dose (typically within 30 minutes prior) to assess the lowest concentration of the drug in the bloodstream, ensuring therapeutic levels and minimizing toxicity—especially important for nephrotoxic drugs like vancomycin.
Which statement by the nurse best reflects compassionate advocacy for a client struggling to afford their medications?
A. "That’s not really my concern, but I can refer you to billing."
B. "I’ll talk to the provider to see if we can find a more affordable alternative."
C. "Just take half the dose until your next paycheck."
D. "You should’ve told us sooner."
Correct answer: B. "I’ll talk to the provider to see if we can find a more affordable alternative."
Rationale: Advocating for client access to medications is a vital part of compassionate nursing care.