WGU D116 Advanced Pharmacology Unit 2: Pharmacokinetics & Pharmacodynamics MASTERY GUIDE 2025 – 44 Expert-Curated Q&A with Detailed Rationales, Drug Mechanisms, and Clinical Applications

A patient receives a drug that has a narrow therapeutic range. What is the nurse administering this medication expected to do?

Monitor plasma drug levels

Narrow therapeutic range is more difficult to administer safely because the difference between MEC and toxic concentration is small

A patient is receiving intravenous gentamicin. A serum drug test reveals toxic levels. The dosing is correct, and this medication has been tolerated by this patient in the past.

What is a probable cause of the test result?

The pt is taking another medication that binds to serum albumin

BGentamicin binds to albumin but weakly. In presence of another drug that binds to albumin, gentamicin can rise to toxic levels in blood stream

What are the components of pharmacokinetics?

Absorption, distribution, metabolism, excretion

Does the volume of distribution increase or decrease as the concentration of a drug in the blood plasma increases?

DECREASES

A patient reports becoming "immune" to a medication because it no longer works to alleviate symptoms.

The provider recognizes that this decreased effectiveness is likely caused by what?

Desensitization of receptor sites by continual exposure to the drug

Continual exposure to an agonist would cause the cell to become less responsive or desensitized

What occurs when a drug binds to a receptor in the body?

It increases or decreases the activity of that receptor

Which pharmacodynamic principle is most correlated with drug toxicity?

Therapeutic index

Which is calculated by dividing the median toxic dose by the median efficacious dose

A patient who is taking morphine for pain asks the nurse how a pain medication can also cause constipation.

What is the nurse's response?

It is selective to receptors that regulate more than one body process

Which statement about food and drug interactions is true?

Some foods can inhibit CYP isoenzymes and alter drug metabolism

Grapefruit inhibits which lowers metabolism of drugs, leading to toxic effects of drugs

With respect to the cytochrome P450 (CYP) system, what will result in a higher concentration of a drug?

Inhibition of the enzyme

Decreasing enzyme activity leads to decreased metabolism of the drug, leading to toxic effects of drug

An advanced practice registered nurse (APRN) works in a urology clinic under the supervision of a physician who does not restrict the types of medications the APRN is allowed to prescribe. State law does not require the APRN to practice under physician supervision.

How would the APRN's prescriptive authority be described?

Independent because the prescriptive authority does not require the APRN work under physician supervision

Which drug requires registration with the Drug Enforcement Administration (DEA) to prescribe?

Chlordiazepoxide

Schedule IV substance

All scheduled substances require the prescriber to be registered with the DEA

True or False

Your DEA registration allows you to prescribe Schedule II and Schedule III controlled substances for addiction.

FALSE

Special waiver is required

A patient with diabetes reports losing their job and an inability to purchase the required medications.

As the FNP, which action is most appropriate?

Contact a different pharmacy-it could decrease the cost of the medication

A nurse is preparing to administer a drug. After reading the medication guide, the nurse notes that the drug has been linked to symptoms of Parkinson disease in some patients.

What should the nurse do?

Observe the patient closely for such symptoms and prepare to tx them if needed

A drug that causes disease-like s/s is known to be iatrogenic

Iatrogenic effects are not typically expected side effects

True or False

Macrolide antibiotics are classic inducers of common cytochrome enzymes.

False

Macrolide antibiotics are inhibitors

True or False

The World Health Organization (WHO) accounts for the cost to the patient when they consider rational drug use.

True

Accounts for cost, adequate length of therapy, individualized dosing, medication appropriate to the pt's clinical needs

A patient diagnosed with bipolar disorder is prescribed daily lithium.

Which action is most important to determine whether the therapeutic level is maintained?

ensure periodic lab testing is completed

The drug manual states that older adult patients are at increased risk for hepatic side effects.

Which action is most important when prescribing this medication to an 80-year-old patient?

Obtain pretreatment lab work

True or False

Therapeutic drug monitoring promotes standardized dosing.

False

TDM promotes an individualized drug plan based on serum levels of drug and patient outcomes

Which patient would benefit from invasive therapeutic drug monitoring?

The heart failure pt on digoxin

Digoxin is a narrow therapeutic window index and levels need to be drawn frequently to assess for efficacy and toxicity

A patient newly diagnosed with diabetes is to be discharged from the hospital.

Which action should be taken first during medication education?

Asking the pt to demonstrate how to measure and administer insulin

True or False

It is important to document height and weight while performing medication reconciliation.

True

Changes in BMI may alter the volume of meds

Why is it important to consider prototype drugs when studying pharmacology?

They represent the lead agent of a class or family of drugs

Prototype drugs help you understand the family and their differences

Which drug is a prototype nonselective beta-blocker?

Propranolol

Which drug is a third-generation beta-blocker?

Carvedilol

Which drugs are a prototype cardioselective beta-blocker?

Atenolol and metoprolol

PDE 5 inhibitor drugs belong to what drug class?

Afil

Calcium metabolism regulator drugs belong to what drug class?

donate

Antiviral drugs belong to what drug class?

Vir

SGL T2 drugs belong to what drug class?

Glinide

Antimigraine drugs belong to what drug class?

Tiplan

You have a patient who has been on amlodipine for hypertension for the last three months. He is tolerating the medication well. But he has not shown a decrease in blood pressure as you would like. You want to keep this patient on a dihydropyridine calcium channel blocker because of the lack of side effects.

Which drug is a dihydropyridine calcium channel blocker?

Isradipine

-dipine suffix is same as amlodipine

Which factor increases the need for APRNs to have full prescriptive authority?

More patients will have access to healthcare

Limited prescriptive authority creates numerous barriers to quality, affordable, and accessible patient care

An APRN works in a urology clinic under the supervision of a physician who does not restrict the types of medications the APRN is allowed to prescribe. State law does not require the APRN to practice under physician supervision.

How would the APRN's prescriptive authority be described?

Independent

A patient taking three medications for hypertension is diagnosed with chronic obstructive pulmonary disease (COPD).

Which action should be taken prior to prescribing medications to treat COPD?

Obtain a complete medication history

Prior to adding any medications to a patient's regimen, providers need to assess for any drug-drug interactions

A patient with chronic pain calls the provider's office to request a refill for oxycodone.

Which action is most appropriate?

Schedule an appointment with the patient

Schedule 2 meds are not eligible for refills and must be in a hard script - need to be seen by appointment

A patient is using a metered-dose inhaler containing albuterol for asthma. The medication label instructs the patient to administer "two puffs every 4 hours as needed for coughing or wheezing." The patient reports feeling jittery sometimes when taking the medication, and she does not feel that the medication is always effective.

Which action is most appropriate?

Auscultating the patient's lung sounds and obtaining VS

The nurse administers naloxone to a patient who has received a toxic dose of morphine sulfate.

The naloxone is effective because of which action?

Preventing activation of opioid receptors through antagonist actions

Blocks the action of opioids at opioid receptors

The nurse is preparing to administer penicillin G intramuscularly to a child. The child's parents ask why the drug cannot be given in an oral liquid form.

What is the nurse's reply?

"This drug would be inactivated by enzymes in the stomach"

Penicillin G can not be given orally because of this. Penicillin G does not have a narrow therapeutic range

Ipratropium bromide is a quaternary ammonium derivative of the prototype drug atropine. It is used for bronchodilation.

Why would a medicinal chemist want to alter this prototype?

To allow for higher doses to be delivered

Causes greater bronchodilation with less toxicity from systemic absorption

Bradykinin cough is not present in what type of medications?

Angiotension 2 receptor antagonists/blocker (ARBs)

those type of medications end in -sartan

Sildenafil is a prototype of phosphodiesterase type 5 inhibitors (PDE5 inhibitors) that Pfizer launched as Viagra.

Which drug is also a PDE5 inhibitor?

Tadalafil

suffix -fil says it is a PDE5 family of drugs

What is a common side effect of angiotensin-converting enzyme inhibitors (ACE inhibitors)?

Persistent dry cough

Those medications end in -pril