Pharmacokinetics_Pharm

31問 • 2年前

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An 18-year old woman is brought to the ED due to durg overdose. Which route of the administration is the most desirable for administration is the most desirable for administering the antidote for the drug overdose?

Drug A is a weakly basic drug with a pKa of 7.8. If administred orally, at which of the following sites of absorption will the drug be able to readily pass through the membrane?

Jejunum (pH 8.0)

KR2250 in an investigational cholestrol-lowering agent. KR2250 has a high molecular weight and is extensively bound to albumin. KR2250 will have a(n)_____apparent Vd.

Low

A 40-year old man (70 kg) was recently diagnosed with infection involving methicilliln-resistant Staph A. He received 2000 mg of Vancomycin as an IV loading dose. The peak plasma concentration of Vancomycin was 28.5 mg/L. The apparent Vd is:

1 L/kg

A 55-year old woman is brought to the ED because of seizures. She has a history of renal disease and currently undergoes dialysis. She receives an IV infusion of antiseisure Drug X. Which is the most likely to be observed with the use of Drug X in the is patient?

Increased Half-Life and Decreased Dosage

Ritonavir is coadministered with other anti-HIV drugs to boost their pharmacokinetics. Which property of Ritonavir is responsible for improving the pharmacokinetics of other anti-HIV drugs?

CYP450 inhibition

Which of the following reactions represents Phase II of drug metabolism?

Sulfation

A pharmacokinetic study of a new anti-hypertensive drug being conducted in healthy human volunteers. The half-life of the drug after administration by continuous IV infusion is 12 hours. Which of the following best approximates the time for the drug to reach steady state?

60 hours

A 64-year old woman (60 kg) is treated with experimentatal Drug A for DM II. Drug A is available as tablets with an oral bioavailability of 90%. If the Vd is 2L/kg and the desired steady-state plasma concentration is 3.0 mg/L, which of the following is the most appropriate oral loading dose of Drug A?

400 mg

Valproic acid is highly protein-bound drug commonly used as an antiepiletic agent. In which disease state should the dose valproic acid be reduced to avoid ADEs?

Hypoalbuminemia

Which of the following best describes how a drug that acts as an agonist at the A subtype of GABA receptors affects signal transduction in a neuron?

Activation of this receptor subtype open ion channels that allow chloride to enter cells and decreases the chance of generating an action potential

If 1 mg of Lorazepam produces the same anxiolytic response as 10 mg of Diazepam, which of the following is correct?

Lorazepam is more potent than Diazepam

If 10 mg of oxycodone produces a greater analegesic response than does aspirin at any dose, which of the following is correct?

Oxycodone is more efficacious than is aspirin

Diazepam, Flumazenil, and the experimental drug RO15-4513 all bind reversibly to the benzodiazepine receptor. Diazepam is the classic agonist for this receptor, and when it occupies the receptor, it decreases the chance of neuronal hyperexcitability, thereby decreasing seizure sensitivity. When Flumazenil binds to the benxodiazepine receptor, it does not alter neuronal hyperexcitability or seizure sensitivity. Which of the following best describes the activity of Flumazenil?

Competitive antagonist

In the presence of picrotoxin, diazepam is less efficacious at causing sedation, regardless of the dose of diazepam. Picrotoxin has sedative effect, even at the highest dose. Which of the following is correct regarding these agents?

Picrotoxin is a noncompetitive antagonist

When albuterol bind to the beta-adrenergic receptor, it dissociates after a few milliseconds. However, its cellular actions las for hundreds of milllisecondsdue to the generation of second messanger molecules whose actions on effector systems take longer to occur. Which of the following best describes this phenomenon?

Signal amplification

If there were spare beta(1)-adrenergic receptors on cardiac muscle cells, which of the following statements would be correct?

A maximal effect of epinephrine is seen when only a portion of beta(1)-adrenergic receptors are occupied

Which of the following upregulates postsynaptic alpha(1)-adrenergic receptors?

Daily use of prazosin, and alpha(1)-receptor antagonist

Methylphenidate helps patients with ADHD maintain attention and perform better at school work, with an ED(50) of 10 mg. However, methlyphenidate can also cause significant nausea at higher doses [TD(50) = 30 mg]. Which of the following is correct regarding methylphenidate?

The therapeutic index of methylphenidate is 3

Which of the following is correct concerning the safety of using Warfarin (with a small therapeutic index) vs. Penicillin (with a large therapeutic index)?

Warfarin treatment has a high chance of resulting in dangerous adverse effects if bioavailability is altered

Because calcium channel blockers undergo significant first-pass metabolism, which of the following responses would you expect to occur if a patient with cirrhosis was prescribed a calcium channel blocker?

The drug’s half-life would be altered

Which of the following types of drugs will have maximum oral bioavailability?

Largely hydrophobic, yet soluble in aqueous solutions

A patient is taking Drug A that is highly metabolized by the cytochrome P-450 system. He has been on the drug for 6 months. He has now been started on a second drug (Drug B) that is an inducer of cytochrome P-450. You should be aware to monitor for:

Decreased therapeutic effects of Drug A

A 40 year old patient who weighs 70 kg. was recently diagnosed with infections from MRSA. He received 2000 mg of Vancomycin as an IV loading dose. The peak concentration was reported to be 28 .5 mg/L/ The apparent volume for distribution is:

1 L/kg

The margin of safety between the dose needed to produce benefits and the dose needed to cause harmful to toxic effects is known as the

Therapeutic index

A drug with a 1⁄2 life of 10 hours is administered by continuous IV infusion. Which of the following best approximated the time for the drug to reach steady state?

50 hours

Which of the following is not one of the four parameters of pharmacokinetics?

Tachyphylaxis

The primary organ of drug metabolism is the:

Liver

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?

Naloxone is a competitive antagonist

In the presence of Pentazocine [Talwin], a higher concentration of Morphine is required to elicit full pain relief. Pentazocine [Talwin] by itself has a smaller analgesic effect than does Morphine, even at the highest dose. Which of the following is correct regarding these medications?

Morphine is a full agonist, and Pentazocine is a partial agonist

Which of the following would up regulate postsynaptic B1 adrenergic receptors?

Daily use of Propranolol, a B1 receptor antagonist

Patho Renal

Two Clean Queens · 100問 · 2年前

Patho Renal