[Test4] General principles of pharmacology

Which of the following statements about important historical milestones in U.S. Food and Drug Laws is NOT correct?

A. The Harrison Narcotic Act of 1914 mandated standards for drug purity and strength, and directions for synthesis.

B. The Durham-Humphrey Amendment of 1951 identified non-narcotic drugs that cannot be safely used without medical supervision and prohibited their sale without a prescription by a licensed practitioner.

C. The Controlled Substances Act (CSA) of 1970 collected all legislations related to drugs with abuse potential, placed the drugs in schedules, and created a “closed” system for legitimate manufacturing, distribution, and dispensing of such drugs.

D. The current list of controlled substances can be found in the most recent update of Title 21, Section 1308, Code of Federal Regulations.

The FDA has specific requirements on content and format of labeling for human prescription drugs and biological products.

A. True

B. False

Which of the following statements accurately describes the strength of different types of drug-receptor bonds?

A. Van der Waals forces create strong, irreversible bonds between drugs and receptors.

B. Hydrogen bonds and ionic bonds are of intermediate strength and can be easily broken, allowing for reversible drug-receptor interactions.

C. Covalent bonds are weak and easily broken, which allows for transient drug-receptor interactions.

D. All drug-receptor interactions are equally strong, regardless of the type of bonding involved.

Which of the following statements about drugs-receptor interactions is NOT correct?

A. Drugs can interact with transmembrane ion channels, which may be voltage-gated or ligand-gated.

B. Drugs can interact with transmembrane G protein-coupled receptors and transmembrane receptors with linked enzymatic domains.

C. Drugs can interact with intracellular receptors known as cytoplasmic or nuclear adhesion receptors.

D. Drugs can interact with extracellular receptors, which may be structural proteins, signaling molecules, or soluble cytokines such as TNF-α.

The graded dose-response curve demonstrates the average effect of a drug, as a function of its dose, in a population of individuals from which three important parameters can be deduced: effectiveness, toxicity, and lethality.

A. True

B. False

A drug that favors binding to its active receptor, stabilizes its active conformation, and produces a pharmacological effect is called ________________.

A. An agonist.

B. An inverse agonist.

C. A full agonist.

D. A partial agonist.

Which of the following statements about receptor antagonists is true?

A. A receptor antagonist can only bind to the agonist binding site, preventing the agonist from activating the receptor.

B. Binding of an antagonist to an allosteric site enhances the affinity of the agonist for its binding site.

C. Antagonism can occur at either the agonist binding site or an allosteric site, and can be classified as competitive or noncompetitive.

D. Noncompetitive antagonists can be displaced by high concentrations of the agonist at the agonist binding site.

Which of the following statements about drug pharmacokinetics is correct?

A. A drug must be excreted before it can interact with its target receptor and elicit a pharmacologic effect.

B. Only the receptor-bound fraction of a drug in systemic circulation has a pharmacologic effect.

C. Passive diffusion is effective for transporting large, polar molecules across lipid bilayer membranes.

D. The process of pH trapping affects the diffusion of acidic and basic drugs based on their acid dissociation constant (pKa) and the pH of the environment.

During the first 90 days (first trimester), organogenesis occurs and thus the fetus is most susceptible to teratogenesis.

A. True

B. False

Which of the following statements about drug distribution and volume of distribution (Vd) is correct?

A. A drug with a low volume of distribution (Vd) is primarily retained within the vascular compartment and does not effectively reach target tissues.

B. Plasma protein binding of drugs, such as to albumin, increases the availability of free drug for diffusion into tissues.

C. Two drugs with equal potency will have the same initial dosing requirements regardless of their volume of distribution.

D. A drug that is highly distributed in body tissues will have a lower initial dose requirement to achieve a therapeutic plasma concentration compared to a drug that is less distributed.

Which of the following statements accurately describes the processes involved in drug metabolism and biotransformation?

A. All drugs are inherently active and do not require conversion to exert their therapeutic effects.

B. Prodrugs are inactive compounds that must be converted into active drugs, often through oxidation/reduction reactions.

C. The cytochrome P450 enzyme system is primarily responsible for conjugation reactions that enhance the clearance of drugs.

D. Conjugation and hydrolysis reactions typically convert drugs into smaller, non-polar molecules to facilitate their excretion.

Which of the following statements about drug metabolism and excretion is correct?

A. Most drugs are primarily excreted through bile, respiratory, and dermal routes rather than renal excretion.

B. The rate of drug metabolism and excretion is independent of blood flow to the organs involved.

C. Most drugs follow first-order kinetics, where the rate of metabolism and excretion is proportional to the concentration of the free drug in plasma.

D. Zero-order kinetics indicates that the rate of metabolism and clearance increases with increasing plasma drug concentrations.

A loading dose, i.e., a much higher initial dose than would be required if the drug were retained in plasma, may be used to achieve therapeutic levels with only one or two doses of drug.

A. True

B. False

Which of the following statements about pharmacotherapy and drug response is accurate?

A. Pharmacotherapy is solely dependent on the pharmacokinetic properties of a drug, without consideration of pharmacodynamic principles or patient-related factors.

B. Genetic polymorphisms can lead to inter-individual variations in drug response due to alterations in drug-receptor interactions or metabolic pathways.

C. An individual who is hyporeactive to a drug will always require lower doses than average to achieve the desired therapeutic effect.

D. Tolerance that develops slowly over time due to repeated exposure to a drug is known as tachyphylaxis.

Which of the following statements regarding drug dosing is correct?

A. The individual effective dose of a drug is typically expressed in terms of milliliters per kilogram of body weight.

B. The maximum recommended dose (MRD) provided by manufacturers is based on a healthy adult weighing 75 kg (165 lbs).

C. Patient weight is the only factor to consider when determining the optimal therapeutic dose of a drug for an individual.

D. Dynamic and kinetic variables related to a specific patient do not influence the determination of the optimum therapeutic dose.

Milk is generally more acidic (pH 6.8) than plasma (pH 7.4); therefore, acidic drugs become more concentrated in milk because of the phenomenon of pH trapping, while basic drugs are limited in their ability to enter milk.

A. True

B. False

Which of the following statements regarding pediatric pharmacotherapy is correct?

A. Dosage forms designed for adults are always appropriate for use in children without any modifications.

B. There is a wealth of specific pharmacokinetic and pharmacodynamic data available for the pediatric population, allowing for precise dosing.

C. Weight-based dosing recommendations are considered the most reasonable approach to calculate the maximum safe dose of a drug for children.

D. Palatability of medications does not significantly affect adherence in the pediatric population.

If drug “X” has a half-life of 12 hours, how long does it take for it to be eliminated from the body?

A. 10 hours

B. 14 hours

C. 24 hours

D. 2.5 days

Which of the following statements about prescribing medications for patients with liver disease is correct?

A. Adverse drug effects in patients with liver disease are primarily due to altered pharmacodynamic processes.

B. The Child-Pugh score is used to estimate the liver's ability to metabolize drugs and guide prescribing decisions.

C. Patients with liver disease do not require any adjustments to their medication dosages.

D. Prescribing precautions related to medications can be found solely in the “Adverse Effects” section of drug labeling.

Which of the following statements about estimating creatinine clearance in patients with chronic renal disease is correct?

A. The Cockcroft-Gault equation is used to calculate the estimated creatinine clearance (eCrCl), which helps determine appropriate drug dosages.

B. The normal range for estimated creatinine clearance (eCrCl) in men and women over 40 years of age is the same, at 87-107 mL/min.

C. The Cockcroft-Gault equation does not account for age when calculating creatinine clearance.

D. After the age of 20, the estimated creatinine clearance remains constant and does not change with age.

Which of the following statements regarding non-adherence to prescribed therapeutic regimens is correct?

A. Non-adherence is solely caused by economic factors and does not involve patient behavior or clinician communication.

B. Intentional non-adherence refers to patients actively choosing not to follow their prescribed regimen, while unintentional non-adherence includes forgetfulness and carelessness.

C. Patients are more likely to be adherent to their medication regimens if they have a poor understanding of their illness and treatment.

D. In children, the primary reason for non-adherence is often a dislike for the medication's packaging rather than its taste or smell.

Legend drugs require a prescription because they are considered to be potentially harmful if not used under supervision by a licensed practitioner who must be registered under Controlled Substances Act of 1970 with the Drug Enforcement Administration.

A. True

B. False

Before prescribing a drug, a licensed practitioner must establish an accurate diagnosis whenever possible; although, at times one may prescribe medications based on a presumptive or working diagnosis.

A. True

B. False

Which of the following statements regarding polypharmacy in the elderly is correct?

A. Polypharmacy refers exclusively to the use of prescription medications and does not include over-the-counter (OTC) drugs or herbal supplements.

B. The risk of adverse drug reactions in elderly patients increases exponentially with the number of medications they are taking.

C. Elderly patients are less likely to experience drug interactions compared to younger adults due to their generally better health.

D. Herbal supplements are always safe for elderly patients and do not interact with prescription medications.

Which of the following statements regarding prescribing during pregnancy is correct?

A. Drugs in category A are considered safe.

B. Drugs in Category B are to be prescribed cautiously.

C. Drugs in category C can never be prescribed.

D. Drugs in category D are considered safe.

When prescribing a controlled substance, in addition to writing the number of tablets or capsules to be dispensed, the amount must also be written-out longhand, e.g., Disp #20 (twenty) tablets.

A. True

B. False