Pharmacology Quizzes

Drug X and Drug Y both bind to the receptor known to bind an endogenous ligand. Drug X can achieve maximal effect (Emax) at a concentration of 10 mg/L. Regardless of drug concentration, Drug Y can only produce 80% of the effect of Drug X. Based on this, Drug Y would be considered which of the following?

a. Competitive antagonist of Drug X at the receptor

b. Noncompetitive antagonist of Drug X at the receptor

c. A partial agonist of the receptor

d. An allosteric modulator of the receptor

c. A partial agonist of the receptor

Which of the following is true regarding the relationship between an agonist and a fixed dose of a competitive antagonist?

a. Higher doses of the agonist are required to reach the same effect as that
achieved for agonist alone
b. Once bound, the agonist can no longer surmount the inhibitory effect regardless of concentration
c. The Emax can never be reached, even at high agonist concentrations
d. Effect will exceed that of the agonist alone

a. Higher doses of the agonist are required to reach the same effect as that
achieved for agonist alone

3. Ticagrelor is a reversible noncompetitive antagonist of the adenosine diphosphate (ADP) P2Y12 receptor on the surface of platelets. Ticagrelor binds to a site other than where ADP (the endogenous ligand) binds to the receptor. Because of this, ticagrelor would be considered which of the following?
a. A partial agonist
b. A positive allosteric modulator
c. A negative allosteric modulator
d. An inverse agonist

c. A negative allosteric modulator

4. True or False: The EC50 is always equal to the equilibrium dissociation constant (Kd) of a given irreversible antagonist
a. True
b. False

b. False

5. Potency is defined as which of the following?
a. The maximal response a drug can produce
b. The dose required to produce a response
c. The concentration of free drug at which half maximal binding occurs
d. The range of plasma concentrations of a drug that will elicit the desired response in a population of patients

b. The dose required to produce a response

1. Which of the following is NOT one of the 5 basic mechanisms of transmembrane signaling?
a. Intracellular receptors for lipid soluble agents
b. Receptor tyrosine kinases
c. Ligand-gated ion channels
d. G-protein coupled receptors
e. Adenyl cyclase receptors

e. Adenyl cyclase receptors

2. True or False: All drug receptors are transmembrane proteins with extracellular and cytoplasmic domains.
a. True
b. False

b. False

3. True or False: The duration of agonist effects can persist even after dug concentrations reach zero.
a. True
b. False

a. True

4. Which of the following is NOT an intracellular second messenger of receptor signaling?
a. Acetylcholine
b. Cyclic adenosine-3 ,5 -monophosphate (cAMP)′ ′
c. Cyclic guanosine monophosphate
d. Diacylglycerol (DAG)

a. Acetylcholine

5. The attenuation of G-protein mediated responses over time, even in the presence of agonist, is defined as which of the following?
a. Coupling
b. Phosphorylation
c. Desensitization
d. Antagonism

c. Desensitization

1. The ED50 of Drug X is 250mg and the ED50 of Drug Y is 1gm. Which of the following is true regarding the potency of these drugs?
a. Drug X is 3 times less potent than Drug Y
b. Drug X is 4 times more potent than Drug Y
c. Drug Y is 4 times more potent than Drug Y
d. It is impossible to determine drug potency from the information provided

b. Drug X is 4 times more potent than Drug Y

2. True or false: Quantal dose-effect curves indicate the maximal efficacy of a drug.
a. True
b. False

b. False

3. The range between the minimum toxic dose and the minimum therapeutic dose is defined as which of the following?
a. Therapeutic index
b. Therapeutic window
c. Therapeutic equivalence
d. Therapeutic tolerance

b. Therapeutic window

4. True or false: It is desirable for a drug to have a large therapeutic index.
a. True
b. False

a. True

5. Rapidly diminishing response after administration of a drug is defined as which of the following?
a. Hyporeactivity
b. Hypersensitivity
c. Tolerance
d. Tachyphylaxis

d. Tachyphylaxis

Which of the following statements accurately describes a potential drug interaction between verapamil, a non-dihydropyridine calcium channel blocker, and simvastatin?

a. Verapamil and simvastatin give concurrently no clinical effects

b. Verapamil may potentiate the myopathic effects of simvastatin, increasing risk of rhabdomyolysis

c. Verapamil can increase metabolism of simvastatin, reducing its efficacy

d. Verapamil may enhance the antihypertensive effects of simvastatin, leading to hypotension

b. Verapamil may potentiate the myopathic effects of simvastatin, increasing risk of rhabdomyolysis

Simvastatin, a commonly used HMG-CoA reductase inhibitor is extensively metabolized by CYP3A4, was started on a patient taking verapamil. Verapamil (nonDHP CCB) causes an increase in serum concentration of simvastatin. What is the mechanism of action of this drug interaction?

a. Induction of CYP3A4

b. Autoinduction of simvastatin

c. Additive effects of both drugs

d. pharmaceutical drug interaction

e. Inhibition of CYP3A4

e. Inhibition of CYP3A4

Which beta blockers should be avoided in patients who use albuterol (a beta2- agonist) PRN for asthma?

a. Metoprolol succinate (beta-blocker (beta 1 selective))

b. Carvedilol (beta-blocker (nonselective))

c. All beta blockers can be used concurrently with a beta 2 agonist

d. all beta blockers should be avoided in any patient on albuterol

b. Carvedilol (beta-blocker (nonselective))

A drug interaction was found between a Beta Blocker and an Beta2-agonist, as some beta blockers will block the pharmacological effects of beta2-agpnists. Which is likely the object drug?

a. Beta Blocker

b. Beta2- agonist

b. Beta2- agonist

The concomitant use of two or more drugs that may lower blood pressure is often clinically appropriate.

True or False?

True

A patient is taking a 5-day course of tamsulosin, an Alpha-1 Blocker. The patient comes to the pharmacy to pick up lisinopril (ACEi), for which she has been taking for the last year, the pharmacist notices the drug interaction between the tamsulosin and lisinopril. What should the pharmacist recommend.

a. discontinue the precipitant drug

b. this interaction has no clinical effects

c. discontinue the object drug

d. recommend no changes to the medications

d. recommend no changes to the medications

What is the type of drug interaction is seen between a loop diuretic (ex furosemide) and an angiotensin-converting enzyme inhibitors (ex lisinopril) as the combination can cause an exaggerated hypotensive response?

a. additive hypotensive effects

b. synergistic hypotensive effects

c. idiosyncratic hypotensive effects

d. antagonistic hypotensive effects

e. none of the above

b. synergistic hypotensive effects

What is the type of drug interaction seen between an alpha-1 blocker (doxazosin) and an ARB (Valsartan) as they have similar mechanisms for managing blood pressure?

a. additive hypotensive effects

b. synergistic hypotensive effects

c. idiosyncratic hypotensive effects

d. antagonistic hypotensive effects

e. none of the above

a. additive hypotensive effects

Loop diuretics may enhance the hypotensive effect and the nephrotic effects of Angiotensin-Converting Enzyme Inhibitors. What drug is the precipitant drug?

a. Loop Diuretics

b. Angiotensin-Converting Enzyme Inhibitors

a. Loop Diuretics**

What monitoring parameters would be important for the pharmacist in a patient on both an alpha-1-blocker (doxazosin) and an ARB (Valsartan)?

a. Electrolyte abnormalities

b. Bood Pressure readings

c. PO intake

d. Creatinine Clearance

e. Blood Glucose readings

b. Bood Pressure readings