Estás en modo de exploración. debe iniciar sesión para usar MEMORY

level: pre test

Questions and Answers List

level questions: pre test

Question	Answer
Of the many types of data plots that are used to help explain the pharmacodynamics of drugs, which plot is very useful for determining the total number of receptors and the affinity of a drug for those receptors in a tissue or membrane?	Double-reciprocal plot
Which route of administration is most likely to subject a drug to a firstpass effect?	Oral
Two drugs may act on the same tissue or organ through independent receptors, resulting in effects in opposite directions. This is known as	Physiologic antagonism
A new aminoglycoside antibiotic (5 mg/kg) was infused intravenously over 30 min to a 70-kg volunteer. The plasma concentrations of the drug were measured at various times after the end of the infusion, as recorded in the table and shown in the figure below	Questions 4–7
The elimination half-life (t1/2) of the aminoglycoside in this patient was approximately	3.1 h
The elimination rate constant (ke) of the aminoglycoside in this patient was approximately	0.22 h−1
The apparent volume of distribution (Vd) of the drug in this patient was approximately	50 L
The total body clearance (CLtotal) of the drug in this patient was approximately	11 L/h
If a drug is repeatedly administered at dosing intervals that are equal to its elimination half-life, the number of doses required for the plasma concentration of the drug to reach the steady state is	4 to 5
If a drug is repeatedly administered at dosing intervals that are equal to its elimination half-life, the number of doses required for the plasma concentration of the drug to reach the steady state is	4 to 5
The pharmacokinetic value that most reliably reflects the amount of drug reaching the target tissue after oral administration is the	Area under the blood concentration-time curve (AUC)
It was determined that 95% of an oral 80-mg dose of verapamil was absorbed in a 70-kg test subject. However, because of extensive biotransformation during its first pass through the portal circulation, the bioavailability of verapamil was only 25%. Assuming a liver blood flow of 1500 mL/min, the hepatic clearance of verapamil in this situation was	1425 mL/min
Drug products have many types of names. Of the following types of names that are applied to drugs, the one that is the official name and refers only to that drug and not to a particular product is the	Generic name
Which of the following is classified as belonging to the tyrosine kinase family of receptors?	Insulin receptor
Identical doses of a capsule preparation (X) and a tablet preparation (Y) of the same drug were compared on a blood concentration-time plot with respect to peak concentration, time to peak concentration, and AUC after oral administration as shown in the figure below. This comparison was made to determine which of the following?	Bioequivalence
Of the following characteristics, which is unlikely to be associated with the process of facilitated diffusion of drugs?	The drug crosses the membrane against a concentration gradient and the process requires cellular energy
In comparing the following possible routes, which is associated with the excretion of quantitatively small amounts of drugs or their metabolic derivatives?	Milk
Of the following, which is a phase II biotransformation reaction?	Sulfate conjugation
Which of the following is unlikely to be associated with oral drug administration of an enteric-coated dosage form?	Variability in absorption caused by fluctuations in gastric emptying time
Of the following, which is unlikely to be associated with receptors bound to plasma membranes, their interaction with ligands, and the biologic response to this interaction?	Activation of membrane-bound receptors and subsequent intracellular events elicit a biologic response through the transcription of DNA
9. Of the following, which is unlikely to be associated with the binding of drugs to plasma proteins?	Plasma protein binding generally limits renal tubular secretion and biotransformation
Of the following, which is unlikely to be associated with drug distribution into and out of the central nervous system (CNS)?	Strongly ionized drugs freely enter the CNS through carrier-mediated transport systems
The greater proportion of the dose of a drug administered orally will be absorbed in the small intestine. However, on the assumption that passive transport of the nonionized form of a drug determines its rate of absorption, which of the following compounds will be absorbed to the least extent in the stomach?	Propranolol (pKa = 9.4)
For each type of drug interaction below, select the pair of substances that illustrates it with a reduction in drug effectiveness: :Therapeutic interaction	Isoproterenol and propranolol
For each type of drug interaction below, select the pair of substances that illustrates it with a reduction in drug effectiveness:Physical interaction	Soap and benzalkonium chlorid
For each type of drug interaction below, select the pair of substances that illustrates it with a reduction in drug effectiveness:Chemical interaction	Tetracycline and milk
For each description of a drug response below, choose the term with which it is most likely to be associated: Immunologically mediated reaction to drug observed soon after administration	Anaphylaxis
For each description of a drug response below, choose the term with which it is most likely to be associated:A rapid reduction in the effect of a given dose of a drug after only one or two doses	Tachyphylaxis
For each description of a drug response below, choose the term with which it is most likely to be associated: Hyperreactivity to a drug seen as a result of denervation	Supersensitivity
For each component of a time-action curve listed below, choose the lettered interval (shown on the diagram) with which it is most closely associated:Time to peak effect	T to W
Time to onset of action	T to U
Duration of action	U to Y
For each description below, select the transmembranal transport mechanism it best defines:Lipid-soluble drugs cross the membrane at a rate proportional to the concentration gradient across the membrane and the lipid:water partition coefficient of the drug	Simple diffusion
Bulk flow of water through membrane pores, resulting from osmotic differences across the membrane, transports drug molecules that fit through the membrane pores	Filtration
After binding to a proteinaceous membrane carrier, drugs are carried across the membrane (with the expenditure of cellular energy), where they are released	Active transport
Lipid-soluble xenobiotics are commonly biotransformed by oxidation in the drug-metabolizing microsomal system (DMMS). For each description below, choose the component of the microsomal mixed-function oxidase system with which it is most closely associated: A group of iron (Fe)-containing isoenzymes that activate molecular oxygen to a form that is capable of interacting with organic substrates	Cytochrome P450
The component that provides reducing equivalents for the enzyme system	Nicotinamide adenine dinucleotide phosphate (NADPH)
A flavoprotein that accepts reducing equivalents and transfers them to the catalytic enzyme	NADPH–cytochrome P450 reductase
A 19-year-old male being treated for leukemia develops fever. You give agents that will cover bacterial, viral, and fungal infections. Two days later, he develops acute renal failure. Which drug was most likely responsible?	Amphotericin B
A 26-year-old female with acquired immunodeficiency syndrome (AIDS) develops cryptococcal meningitis. She refuses all intravenous medication. Which antifungal agent can be given orally to treat the meningeal infection?	Fluconazole
Why is vitamin B6 usually prescribed with isoniazid (INH)?	It prevents some adverse effects of INH therapy
The quinolone derivative that is most effective against Pseudomonas aeruginosa is	Ciprofloxacin
A 19-year-old woman is diagnosed with tuberculosis (TB). Before prescribing a drug regimen, you take a careful medication history because one of the drugs commonly used to treat TB induces microsomal cytochrome P450 enzymes in the liver. Which drug is this?	Rifampin
The elimination half-life of which of the following tetracyclines remains unchanged when the drug is administered to an anuric patient?	Doxycycline
In the treatment of bacterial meningitis in children, the drug of choice is	Ceftriaxone
In patients with hepatic coma, decreases in the production and absorption of ammonia from the gastrointestinal (GI) tract will be beneficial. The antibiotic of choice in this situation would be	Neomycin
Indicate from the diagram below the site of action of penicillinase	E
Clavulanic acid is important because it	Inactivates bacterial β-lactamases
In the treatment of infections caused by P. aeruginosa, the antimicrobial agent that has proved to be effective is	Piperacillin
Ethambutol is administered concurrently with other antitubercular drugs in the treatment of TB in order to	Retard the development of organism resistance
The most active aminoglycoside against Mycobacterium tuberculosis is	Streptomycin
The drug used in all types of TB is	INH