Question 1

How do genetic/genomic issues influence individual variation in the response to a specific drug?&#10;A)Polymorphisms of genes encoding metabolizing enzymes&#10;B)Age-related loss of alleles within the cells lining the intestinal tract&#10;C)Single-gene disorders that reduce the function of the kidneys or the liver&#10;D)Genetic-based behavior problems that promote poor adherence to prescribed drug regimens

Accepted Answer

The variations in individual drug response are based on polymorphisms in genes coding for metabolizing enzymes, transporters, and receptors. These polymorphisms are very common, whereas single-gene disorders of any type are not common. Loss of alleles has not been associated with the aging process. Behavioral problems are poorly understood, as are the genetic bases of specific behaviors.

Question 2

What would be the patient's response to a normal drug dose that, because of a genetic variation in an enzyme that prepares the drug for elimination, results ina blooddrug level that is below the minimum effective concentration (MEC)?

A)Drug entry exceeds drug elimination.
B)The risk for toxic side effects is increased.
C)The intended response fails to be produced.
D)The drug's duration of action is longer than expected.

Accepted Answer

In order for a drug to produce its intended response, its blood levels must reach the minimum effective concentration. When enzymes responsible for metabolizing and preparing drugs for elimination are more active as a result of a genetic variation, sensitive drugs are eliminated more rapidly, and a "normal" dose may not be high enough to allow the drug to be retained long enough to reach the MEC.

Question 3

A patient has a very high concentration of insulin receptors on cells that require insulin for glucose to enter. How should insulin dosages be adjusted for this patient to have blood glucose levels within the normal range?

A)Insulin dosages should be given less frequently because the drug will remain bound to receptors longer.
B)Insulin dosages should be decreased because the drug will exert its actions at lower concentrations.
C)Insulin dosages should be given more frequently because the drug will be eliminated at a faster rate.
D)Insulin dosages should be increased because cells will be less sensitive to the presence of active insulin.

Accepted Answer

For insulin or any drug that requires interaction with a receptor to agonize a cell and induce its intended response, an increase in the number of receptors specific to the drug increases the cell's sensitivity to the drug. A smaller dose is needed to produce the response of a lower blood glucose level. Normal dosages could easily cause severe hypoglycemia.

Question 4

Which of the following is a goal of pharmacogenetics?&#10;A)Producing &#34;blockbuster drugs&#34; that will work equally well for everyone&#10;B)Bringing down the cost of pharmaceutical manufacturing&#10;C)Developing drugs that will treat very rare diseases&#10;D)Reducing adverse reactions

Accepted Answer

The pharmacogenetic variations in individual drug response are based on polymorphisms in genes coding for metabolizing enzymes, transporters, and receptors. The clinical responses to these differences can range from life-threatening adverse reactions to a complete lack of therapeutic effect. About 20% of drugs produce adverse reactions that were unknown when the drugs first came to market, and adverse drug reactions are considered one of the leading causes of death. A main goal of pharmacogenomics is the reduction of adverse reactions to medications.

Question 5

What is the expected heart-rate response when a patient is taking a drug that is an adrenaline antagonist?&#10;A)Heart rate is unchanged.&#10;B)Heart rate decreases.&#10;C)Heart rate increases.&#10;D)Heart rate is irregular.

Accepted Answer

Adrenaline (epinephrine) is made in the body and normally binds to heart receptors and increases the heart rate. A drug that is an adrenaline antagonist binds to heart cell receptors nonfunctionally and blocks naturally occurring adrenaline from binding to these cells. As a result, heart rate decreases (and often becomes more regular).

Question 6

How are the actions of naturally occurring estrogen changed when a patient is taking a drug that is an estrogen agonist?&#10;A)Actions are increased.&#10;B)Actions are decreased.&#10;C)Actions are eliminated.&#10;D)Actions are unchanged.

Accepted Answer

An agonist drug has the same effects as the naturally occurring drug. So, taking a drug that is an estrogen agonist increases the effects of the patient's naturally occurring estrogen.

Question 7

Which condition or factor improves the initial bioavailability of a drug agonist that has extensive first-pass loss as a result of the patient's enhanced liver enzymeactivity?&#10;A)Increasing the patient's fluid intake&#10;B)Co-administering the drug with an antagonist&#10;C)Administering the drug by the intravenous route&#10;D)Crushing the oral form of the drug before administration

Accepted Answer

Bioavailability is the percentage of drug present in the bloodstream. When a drug is administered intravenously, it is all (100%) bioavailable initially. Increasing fluid intake does not affect bioavailability regardless of whether the fluid is taken orally or administered intravenously. Administering an antagonist along with a drug agonist would only cancel out or negate the agonist action, not improve the bioavailability. Crushing an oral drug does not prevent first-pass loss or improve bioavailability.

Question 8

What is the most likely outcome for a patient with glucose-6-phosphate dehydrogenase (G6PD) deficiency when he or she takes aspirin or an antimalarial drug?&#10;A)Rapid elimination of the drug with no benefit&#10;B)Liver damage or failure&#10;C)Hemolytic anemia&#10;D)Fluid retention

Accepted Answer

G6PD is an enzyme needed for red blood cells (erythrocytes) to maintain integrity during oxidative stress. Certain drugs, such as aspirin, antimalarials, probenecid, and vitamin K, increase the level of oxidative stress on red blood cells. With a deficiency of G6PD, the increased oxidative stress caused by these drugs leads to rapid destruction of red blood cells that is greater than the rate at which they can be produced by the bone marrow, resulting in hemolytic anemia.

Question 9

Your patient has been identified as a poor metabolizer of a drug that has just been ordered, and the drug is formulated as an active compound. What will be the mostlikely result if you give this active drug at the standard dose?

A)No therapeutic response
B)Increased adverse reactions and possible toxicity
C)Therapeutic response as expected in the general population
D)Drug inactivation occurs more rapidly, and the therapeutic response is limited.

Accepted Answer

Active-compound drugs work as soon as they enter the bloodstream, without further processing. They must undergo metabolism to be made ready for elimination. In people who are poor metabolizers, the blood drug levels are higher, and the drug remains active much longer. As a result, the patient is at higher risk for continued drug actions, including adverse effects and toxic responses. This person would need lower drug doses given less frequently.

Question 10

An Asian American man and his Caucasian wife are both taking warfarin (Coumadin) daily because of atrial fibrillation. The husband asks why he is prescribed amuch-smaller-than-average dose of the drug to keep his international normalized ratio (INR) at 2.0, whereas his wife takes the average dose, even though he is taller and heavier than she is. What is the nurse's best response?

A)"Body size is not important for warfarin, but gender differences are because testosterone improves its action."
B)"You are probably anemic, which would reduce your ability to form blood clots, so your doses can be lower."
C)"Many Asian Americans do not break down warfarin as fast as Caucasians, so the drug is more effective at lower dosages."
D)"Caucasians have higher levels of the enzyme that breaks down warfarin, requiring higher dosages for the same effect on INR."

Accepted Answer

Polymorphisms in the CYP2C9 metabolizing enzyme are common in Asians and Asian Americans. As a result, the drug warfarin remains in the body longer. These individuals require lower dosages to maintain the prescribed INR and avoid serious bleeding. This response is not related to gender or body size.

Question 11

A patient is identified as an ultra-rapid metabolizer for drugs that are prepared for elimination by CYP2D6. What effect will this have on the patient's ability tobenefit from any active drug that is metabolized by this enzyme?

A)Intended responses increase, whereas side effects decrease.
B)Intended responses decrease, whereas side effects increase.
C)Both intended responses and side effects increase.
D)Both intended responses and side effects decrease.

Accepted Answer

The answer of A patient is identified as an ultra-rapid...

Question 12

You are caring for a child with acute lymphoblastic leukemia. She has been genotyped and is homozygous for a TPMT polymorphism, producing very little of the enzymeneeded for this drug's metabolism. How would you expect this to affect dosing of the drug 6-mercaptopurine?

A)This child should receive only a small fraction of the standard dose.
B)This child should receive the drug intravenously rather than orally.
C)This child should receive higher doses than the standard dose.
D)This child should receive the standard dose.

Accepted Answer

The answer of You are caring for a child with...

Question 13

A patient with a fractured elbow in the emergency department states that he needs morphine for pain rather than codeine because the last time he had a painfulinjury,codeine was not effective in managing his pain. What is the nurse's best response or action?

A)Ask the patient how much alcohol he ingests daily.
B)Communicate this information to the admitting physician.
C)Alert the health-care provider that this patient is "drug-seeking."
D)Reassure the patient that he will receive progressively higher dosages of codeine until his pain is controlled.

Accepted Answer

The answer of A patient with a fractured elbow in...

Question 14

Which type of parent compound must undergo first-phase metabolism to produce the intended response after it enters the body?&#10;A)A prodrug&#10;B)An active metabolite&#10;C)An inactive metabolite&#10;D)A sustained-released drug

Accepted Answer

The answer of Which type of parent compound must undergo...

Question 15

Which organ has the greatest concentration of cytochrome P (CYP) 450 enzymes?&#10;A)Stomach&#10;B)Kidney&#10;C)Brain&#10;D)Liver

Accepted Answer

The answer of Which organ has the greatest concentration of...

Question 16

Which statement about agonist and antagonist drugs is true?&#10;A)Both drugs types must interact with receptors to produce their intended responses.&#10;B)The primary target tissues for these types of drugs are invading bacteria and viruses.&#10;C)Antagonists drugs produce only intended responses, and agonist drugs produce both intended responses and side effects.&#10;D)These types of drugs are less likely to cause allergic responses than drugs that are neither agonists nor antagonists.

Accepted Answer

The answer of Which statement about agonist and antagonist drugs...

Question 17

Which processes of drug response are most subject to genetic variation?&#10;A)Drug dissolution in body fluids and drug binding to plasma proteins&#10;B)Rates of drug movement into and through the gastrointestinal tract&#10;C)Drug activation or deactivation and duration of drug actions&#10;D)Drug binding with receptors and drug blocking of receptors

Accepted Answer

The answer of Which processes of drug response are most...

Deck 17: Assessing Genomic Variation in Drug Response