Question 1

Drug X has a strong affinity for a specific receptor, and this enables it to elicit a(n) ____ effect.

Accepted Answer

Drugs with a strong affinity for a specific receptor can act as agonists (activating the receptor), antagonists (blocking the receptor), or mixed agonist/antagonists (both activating and blocking different effects of the receptor), depending on their intrinsic activity at that receptor.

Question 2

Mrs. Peters suffers an acute bronchospasm and receives epinephrine. This drug enhances the normal physiologic function of its beta-2 receptor to stimulate bronchodilation. No new function was developed as a result. Mrs. Peters' epinephrine has a(n) ____ effect.

Accepted Answer

Epinephrine acts as an agonist because it enhances the normal function of the beta-2 receptor, stimulating bronchodilation without introducing a new function.

Question 3

Mr. Clemmens receives a combination of drugs from several different physicians. His newest drug inactivates the receptor so that its agonist cannot be effective, no matter how much the physician is able to increase the agonist's concentration. The newest drug in Mr. Clemmens' regimen is a:

Accepted Answer

A noncompetitive antagonist inactivates the receptor in such a way that an agonist cannot exert its effect, regardless of its concentration. This is because noncompetitive antagonists bind to a different site than the agonist, causing a change in the receptor that prevents the agonist from being effective.

Question 4

Mrs. Jennings takes a new medication, in addition to several she has used for years. The new agent is fairly effective, but it seems to interfere with the action of an older drug that normally has greater efficacy. Mrs. Jennings' new drug is apparently acting as a:

Accepted Answer

The answer of Mrs. Jennings takes a new medication, in...

Question 5

Mrs. Jennings is switched to a drug that resembles the ____ to which an enzyme attaches, resulting in a drug-enzyme interaction.

Accepted Answer

The correct answer is C) substrate. In biochemistry, a substrate is the molecule upon which an enzyme acts. The drug resembling the substrate would interact with the enzyme in a similar manner, leading to a drug-enzyme interaction.

Question 6

The degree to which a drug is able to produce its desired effect is its:

Accepted Answer

Efficacy refers to the maximum effect that a drug can produce, regardless of dose, indicating its ability to achieve its intended effect.

Question 7

Mrs. Jennings' physician is monitoring how long it takes after she administers her medication until she sees or feels the first sign of its effect. The physician is obviously concerned with the drug's:

Accepted Answer

The physician is concerned with both the onset of action, which is the time it takes for a drug to show its initial effects, and the latent period, which essentially refers to a similar concept of delay before the onset of action. Both A and B are correct, making D the correct choice.

Question 8

If a researcher is looking for the highest plasma concentration attained from a dose of a specific drug, he or she would be looking for its:

Accepted Answer

The peak plasma level refers to the highest concentration of a drug in the bloodstream after it has been administered. This is what a researcher would look for to determine the maximum concentration a drug achieves in the body following dosing.

Question 9

To discover the plasma concentrations that produce the desired drug effect without toxicity means to establish the drug's:

Accepted Answer

The therapeutic range of a drug refers to the plasma concentration range that achieves the desired effect without causing toxicity. It is the window between efficacy and adverse effects.

Question 10

After her patient receives a new drug, Dr. Anderson monitors the patient to determine the amount that reaches and remains in the systemic circulation. To determine this accurately, Dr. Anderson would most likely want to monitor the rate and extent of:

Accepted Answer

The rate and extent of a drug reaching and remaining in the systemic circulation can be accurately determined by monitoring drug absorption and distribution (which affects how much of the drug gets into the system and where it goes), the patient's metabolism (which can alter the drug's active form and availability), and the drug's elimination (which determines how long the drug stays in the system). Therefore, all of these factors are relevant.

Question 11

LD50 represents:

Accepted Answer

LD50 stands for the lethal dose for 50% of the population. It is a measure used in toxicology to determine the potential lethality of a substance.

Question 12

A laboratory is testing the relative safety of a drug, producing a ratio that is very close to 1. This calculation suggests that:

Accepted Answer

A ratio close to 1 indicates that the effective dose and lethal dose are nearly the same, meaning the drug is very dangerous as the therapeutic and toxic doses are very close.

Question 13

Mr. Woodward takes an antihistamine and reports that it also has a mild, calming effect on him. His physician tells him that this is not at all unusual. The antianxiety effect of this drug is called a(n):

Accepted Answer

The calming effect Mr. Woodward experiences from the antihistamine, which is not its primary intended action, is considered a side effect. Side effects are secondary effects of drugs that occur in addition to the desired therapeutic effects.

Question 14

Mr. Woodward takes another drug that results in a very uncomfortable immune-mediated response by his body against the drug. It does not seem related to dose. Mr. Woodward has experienced a(n):

Accepted Answer

An allergic reaction is an immune-mediated response that is not related to the dose of the drug, which matches the description of Mr. Woodward's experience.

Question 15

Mr. Woodward takes two drugs at the same time. His physician determines that if the two agents interact with each other, they may produce additive ____ responses to each other.

Accepted Answer

Additive responses can occur with agonist (enhancing the same effect), synergistic (enhancing each other's effects in a way that the combined effect is greater than the sum of their individual effects), or antagonistic (opposing effects that when combined might lead to a net effect that is the sum of their individual effects without enhancement) interactions.

Quiz 4: Pharmacodynamics