deck_8357479 Flashcards
Which of the following types of drugs will have maximum oral bioavailability?A. Drugs with high first-pass metabolism.B. Highly hydrophilic drugs.C. Largely hydrophobic, yet soluble in aqueoussolutions.D. Chemically unstable drugs.E. Drugs that are P-glycoprotein substrates.
C. Largely hydrophobic, yet soluble in aqueoussolutions.
Which of the following is true about the blood–brain barrier?A. Endothelial cells of the blood–brain barrier have slit junctions.B. Ionized or polar drugs can cross the blood–brain barrier easily.C. Drugs cannot cross the blood–brain barrier through specific transporters.D. Lipid-soluble drugs readily cross the blood–brain barrier.E. The capillary structure of the blood–brain barrier is similar to that of the liver and spleen.
D. Lipid-soluble drugs readily cross the blood–brain barrier.
A 40-year-old male patient (70 kg) was recently diagnosed with infection involving methicillin-resistant S. aureus. He received 2000 mg of vancomycin as an IV loading dose. The peak plasma concentration of vancomycin was reported to be 28.5 mg/L. The apparent volume of distribution is:A. 1 L/kg. B. 10 L/kg. C. 7 L/kg. D. 70 L/kg. E. 14 L/kg.
A. Vd = dose/C = 2000 mg/28.5 mg/L = 70.1 L. Because the patient is 70 kg, the apparent volume of distribution in L/kg will be approximately 1 L/kg (70.1 L/70 kg).A. 1 L/kg.
A 65-year-old female patient (60 kg) with a history of ischemic stroke was prescribed clopidogrel for stroke prevention. She was hospitalized again after 6 months due to recurrent ischemic stroke. Which of the following is a likely reason she did not respond to clopidogrel therapy? She is a:A. Poor CYP2D6 metabolizer. B. Fast CYP1A2 metabolizer. C. Poor CYP2E1 metabolizer. D. Fast CYP3A4 metabolizer. E. Poor CYP2C19 metabolizer.
E. Poor CYP2C19 metabolizer.
Which of the following phase II metabolic reactions makes phase I metabolites readily excretable in urine?A. Oxidation.B. Reduction.C. Glucuronidation.D. Hydrolysis.E. Alcohol dehydrogenation.
C. Glucuronidation.
Alkalization of urine by giving bicarbonate is used to treat patients presenting with phenobarbital (weak acid) overdose. Which of the following best describes the rationale for alkalization of urine in this setting?A. To reduce tubular reabsorption of phenobarbital. B. To decrease ionization of phenobarbital.C. To increase glomerular filtration of phenobarbital. D. To decrease proximal tubular secretion.E. To increase tubular reabsorption of phenobarbital.
A. To reduce tubular reabsorption of
A drug with a half-life of 10 hours is administered by continuous intravenous infusion. Which of the following best approximates the time for the drug to reach steady state?A. 10 hours. B. 20 hours. C. 33 hours. D. 40 hours. E. 60 hours.
D. 40 hours
A 55-year-old male patient (70 kg) is going to be treated with an experimental drug, Drug X, for an irregular heart rhythm. If the V is 1 L/kg and the desired steady-state plasm concentration is 2.5 mg/L, which of the following is the most appropriate intravenous loading dose for Drug X?A. 175 mg. B. 70 mg. C. 28 mg. D. 10 mg. E. 1 mg.
A. For IV infusion, Loading dose = (Vd) × (desired steady-state plasma concentration). The Vd in this case corrected to the patient’s weight is 70 L. Thus, Loading dose = 70 L × 2.5 mg/L = 175 mg
An 18-year-old female patient is brought to the emergency department due to drug overdose. Which of the following routes of administration is the most desirable for administering the antidote for the drug overdose?A. Intramuscular. B. Subcutaneous.C. Transdermal. D. Oral.E. Intravenous.
E. Intravenous.
Chlorothiazide is a weakly acidic drug with a pKa of 6.5. If administered orally, at which of the following sites of absorption will the drug be able to readily pass through the membrane?A. Mouth (pH approximately 7.0).B. Stomach (pH of 2.5).C. Duodenum (pH approximately 6.1). D. Jejunum (pH approximately 8.0). E. Ileum (pH approximately 7.0).
B. Stomach (pH of 2.5).
Isoproterenol produces maximal contraction of cardiac muscle in a manner similar to epinephrine. Which of the following best describes isoproterenol?A. Full agonist.B. Partial agonist.C. Competitive antagonist. D. Irreversible antagonist. E. Inverse agonist.
A. Full agonist.
If 10 mg of naproxen produces the same analgesic response as 100 mg of ibuprofen, which of the following statements is correct?A. Naproxen is more efficacious than is ibuprofen.B. Naproxen is more potent than ibuprofen.C. Naproxen is a full agonist, and ibuprofen is a partialagonist.D. Naproxen is a competitive antagonist.E. Naproxen is a better drug to take for pain relief thanis ibuprofen.
B. Naproxen is more potent than ibuprofen.
If 10 mg of morphine produces a greater analgesic response than can be achieved by ibuprofen at any dose, which of the following statements is correct?A. Morphine is less efficacious than is ibuprofen.B. Morphine is less potent than is ibuprofen.C. Morphine is a full agonist, and ibuprofen is a partialagonist.D. Ibuprofen is a competitive antagonist.E. Morphine is a better drug to take for pain relief thanis ibuprofen.
E. Morphine is a better drug to take for pain relief thanis ibuprofen.
In the presence of naloxone, a higher concentration of morphine is required to elicit full pain relief. Naloxone by itself has no effect. Which of the following is correct regarding these medications?A. Naloxone is a competitive antagonist.B. Morphine is a full agonist, and naloxone is a partialagonist.C. Morphine is less efficacious than is naloxone.D. Morphine is less potent than is naloxone.E. Naloxone is a noncompetitive antagonist.
A. Naloxone is a competitive antagonist.
In the presence of pentazocine, a higher concentration of morphine is required to elicit full pain relief. Pentazocine by itself has a smaller analgesic effect than does morphine, even at the highest dose. Which of the following is correct regarding these medications?A. Pentazocine is a competitive antagonist.B. Morphine is a full agonist, and pentazocine is apartial agonist.C. Morphine is less efficacious than is pentazocine.D. Morphine is less potent than is pentazocine.E. Pentazocine is a noncompetitive antagonist.
B. Morphine is a full agonist, and pentazocine is apartial agonist.
In the presence of picrotoxin, diazepam is less efficacious at causing sedation, regardless of the dose. Picrotoxin by itself has no sedative effect even at the highest dose. Which of the following is correct?A. Picrotoxin is a competitive antagonist.B. Diazepam is a full agonist, and picrotoxin is a partialagonist.C. Diazepam is less efficacious than is picrotoxin.D. Diazepam is less potent than is picrotoxin.E. Picrotoxin is a noncompetitive antagonist.
E. Picrotoxin is a noncompetitive antagonist.
Which of the following statements most accurately describes a system having spare receptors?A. The number of spare receptors determines the maximum effect.B. Spare receptors are sequestered in the cytosol.C. A single drug–receptor interaction results in manycellular response elements being activated.D. Spare receptors are active even in the absence of anagonist.E. Agonist affinity for spare receptors is less than theiraffinity for “non-spare” receptors.
C. A single drug–receptor interaction results in manycellular response elements being activated.
Which of the following would up-regulate postsynaptic β1 adrenergic receptors?A. Daily use of amphetamine that causes norepinephrine to be released.B. A disease that causes an increase in the activity of norepinephrine neurons.C. Daily use of isoproterenol, a β1 receptor agonist.D. Daily use of formoterol, a β2 receptor agonist.E. Daily use of propranolol, a β1 receptor antagonist.
E. Daily use of propranolol, a β1 receptor antagonist.
Which of the following is correct regarding the autonomic nervous system (ANS)?A. Afferent neurons carry signals from the CNS to the effector organs.B. The neurotransmitter at the parasympathetic ganglion is norepinephrine (NE).C. The neurotransmitter at the sympathetic ganglion is acetylcholine (ACh).D. Sympathetic neurons release ACh in the effector organs.E. Parasympathetic neurons release NE in the effector organs.
C. The neurotransmitter at the sympathetic ganglion is acetylcholine (ACh).
Which of the following is correct regarding somatic motor neurons?A. The neurotransmitter at the somatic motor neuron ganglion is acetylcholine.B. The neurotransmitter at the somatic motor neuron ganglion is norepinephrine.C. Somatic motor neurons innervate smooth muscles.D. Somatic motor neurons do not have ganglia.E. Responses in the somatic motor neurons aregenerally slower than in the autonomic nervous system.
D. Somatic motor neurons do not have ganglia.
Which of the following physiological changes could happen when a person is attacked by a grizzly bear?A. Increase in heart rate.B. Increase in lacrimation (tears). C. Constriction of the pupil (miosis). D. Increase in gastric motility.
A. Increase in heart rate.
Which of the following changes could theoretically happen in a person when the parasympathetic system is inhibited using a pharmacological agent?A. Reduction in heart rate.B. Constriction of the pupil (miosis).C. Increase in gastric motility.D. Dry mouth (xerostomia).E. Contraction of detrusor muscle in the bladder.
D. Dry mouth (xerostomia).
Which of the following statements is correct regarding the sympathetic and parasympathetic systems?A. Acetylcholine activates muscarinic receptors.B. Acetylcholine activates adrenergic receptors.C. Norepinephrine activates muscarinic receptors.D. Activation of the sympathetic system causes a dropin blood pressure.
A. Acetylcholine activates muscarinic receptors.
Which of the following statements concerning the parasympathetic nervous system is correct?A. The parasympathetic system uses norepinephrine as a neurotransmitter.B. The parasympathetic system often discharges as a single, functional system.C. The parasympathetic division is involved in accommodation of near vision, movement of food, and urination.D. The postganglionic fibers of the parasympathetic division are long compared to those of the sympathetic nervous system.E. The parasympathetic system controls the secretion of the adrenal medulla.
C. The parasympathetic division is involved in accommodation of near vision, movement of food, and urination.