922 Final Questions

Two moles of Drug A and four moles of Reactant B are dissolved in water. A sequential reaction occurs in two steps: Step 1 involves two moles of Drug A reacting with two moles of Reactant B to form two moles of Product R (slow reaction). In Step 2, two moles of Product R react with two moles of Reactant B to form two moles of Product S (fast reaction). Determine the reaction order with respect to Reactant B.

A: Fourth

B: Third

C: Second

D: First

E: Zero

D

Drug X has a molecular weight of 250 g/mole, and the drug is dissolved in water at 10 mg/mL. Determine its molar concentration.

40 mM

Imagine an acid drug Imagine an acid drug with its neutral form AH and ionized form A-. Which is CORRECT?

A: As solution acidity increases, more drug exists in its ionized form [A-].

B: As solution acidity decreases, more drug exists in its neutral form [AH].

C: The drug's pKa is likely 7.

D: The drug's Log P is likely 7

C

You have benzocaine You have benzocaine and procaine. Under what pH conditions can you keep both drugs ionized at more than 50% in an aqueous solution?

A: pH < 3

B: pH > 3

C: pH < 9

D: pH > 9

A

Which method will provide slower measurements yet more accurate results in testing drug solubility?

A: Equilibrium solubility

B: Kinetic solubility

A

Which drug is most lipophilic in its neutral form?

A: Drug D

B: Drug E

C: Drug F

D: Drug G

C

Which is an example of zero-order reaction?

A: Drug dimerization in water

B: Drug dimerization in suspension

C: Drug hydrolysis in water

D: Drug hydrolysis in suspension

D

The Arrhenius equation can be used to derive QdT, which is defined as the change in reaction rate between two temperatures. QdT is also useful for determining storage times, such as shelf-life and half-life. Which of the following is CORRECT?

A: QdT = Q10 when initial storage temperature is 10.

B: QdT = Final storage temperature / Initial storage temperature

C: QdT = Initial rate constant / Final rate constant

D: QdT = Initial half-life / Final half-life

E: QdT = Final half-life / Initial half-life

D

Drug YY is stored at 20°C, and its degradation activation energy is 18 kcal/mole. If the storage temperature increased to 40°C, how much will the rate constant increase? Estimate the increase from the figures below.

A: 2 fold

B: 3 fold

C: 4 fold

D: 9 fold

E: 16 fold

D

Which statement is INCORRECT in describing the properties of the drug stored in each pH range (A, B, C, or D)?

A: In pH range A, drug degradation is catalyzed by acid.

B: In pH range B, drug degradation rate is the slowest.

C: In pH range C, drug degradation follows a first-order reaction.

D: In pH range D, the drug has the longest shelf-life

D

The drug described in this monograph is stored at pH 8 and 25°C. Estimate its approximate half-life.

A: 3 minutes

B: 20 minutes

C: 3 hours

D: 20 hours

E: infinite (no degradation)

D

What is 'catalysis by hydroxide ion in an aqueous solution' called?

A: Specific acid catalysis

B: Specific base catalysis

C: General acid catalysis

D: General base catalysis

E: Nucleophilic catalysis

B

Two moles of Drug A and 4 moles of Reactant B are dissolved in water. Consider a sequential reaction occurs in two steps. Step 1: 2 moles of Drug A and 2 moles of Reactant B react to form 2 moles of Product R (Slow reaction). Step 2: 2 moles of Product R react with 2 moles of Reactant B to form 2 moles of Product S (Fast reaction). Determine the correct expression of overall reaction.

A: [ Drug A ] + [ Reactant B ] -> [ Product S ]

B: [ Drug A ] + 2 [ Reactant B ] -> [Product S ]

C: [ Drug A ] + [ Reactant B ]^2 -> [ Product S ]

D: 2[ Drug A ] + 2[ Reactant B ] + 2[ Product R ] -> [ Product S ]

E: 2[ Drug A ] + 4 [ Reactant B ] + 2[ Product R ] -> [ Product S ]

B

Which is NOT an example of first-order reaction?

A: Radioactive decay

B: Hydrolysis of a drug in aqueous solution

C: Drug elimination from the bloodstream following injection

D: Passive drug permeability across cell membranes

E: Biomolecular substitution reactions

E

Which bond would break as the drug molecule shown below undergoes hydrolysis?

A: a

B: b

C: c

D: d

E: e

B

Which drug(s) is(are) most soluble in water at pH 8?

A: Drug D

B: Drug E

C: Drug F

D: Drug G

E: Drugs D and F

B

In normal physiology hyperglycemia will trigger all the following except

A: Increase insulin production in the body

B: Increase gluconeogenesis in the body

C: Cells and tissues store glucose using glucagon

D: b and c

E: a and b

D

Which of the following substances can most easily cross the blood-brain barrier?

A: large protein

B: hydrophobic molecules

C: non-ionized molecules

D: b and c

E: none of the above

D

A patient is receiving 15 mg/hr of a drug via continuous IV infusion. You plan to switch them to an oral formulation given b.i.d., which has a 40% bioavailability. The oral dose per administration should be __1__ mg orally b.i.d.

72

A patient has been taking 600 mg of Drug X orally every 8 hours. The oral bioavailability of Drug X is 60%. If they need to be switched to a continuous IV infusion, what should the infusion rate be to maintain the same systemic drug exposure? __1__ mg/hr.

125

Which of the following is a type of drug-receptor protein that includes such as insulin?

A: multi-subunit ion channels

B: protein kinases

C: transcription factors

D: enzyme-linked receptor

E: G protein coupled receptor.

D

You are given the task of using in vitro tests to find the most potent GPCR agonist. When analyzing your data, the biomarker that you need to screen for is

A: bioavailability

B: EC50

C: AUC po

D: Emax

E: MTC

B

This dose-response curve shows the concentration-dependent effects of norepinephrine on arterial blood pressure, both alone and in the presence of a fixed concentration of Drug X. What is to role of Drug X?

A: full agonist

B: partial agonist

C: competitive antagonist

D: noncompetitive antagonist

E: prodrug

D

In the presence of propranolol, a higher concentration of epinephrine is required to elicit full anti-asthmatic activity. Propranolol does not influence asthma symptoms. Which is correct regarding these medications?

A: epinephrine is less efficacious than is propranolol.

B: epinephrine is a full agonist, and propranolol is a partial agonist.

C: epinephrine is an agonist, and propranolol is a competitive antagonist.

D: epinephrine is an agonist, and propranolol is a non-competitive antagonist.

E: none of the above

C

Using vomiting as an unwanted side effect, what would be the estimated therapeutic index for this drug?

A: 0.1

B: 1

C: 10

D: 100

E: 1000

D

Which of the following factors is least likely to influence drug penetration into the CNS?

A: Lipid solubility

B: Molecular size

C: Degree of ionization

D: The Half-life of the drug in plasma

E: Neurological disease

D

Which of the following characteristics would allow a drug to cross the blood-brain barrier most easily?

A: Large molecular size and hydrophilic nature

B: Small molecular size and lipophilic nature

C: High plasma protein binding and hydrophilicity

D: Ionized form at physiological pH

E: none of the above

B

For a drug eliminated only by filtration, protein binding will decrease the elimination half-life.

True

False

False

Prodrugs can enhance the therapeutic efficacy and reduce adverse effects via different mechanisms including shortened half-life

True

False

False

The patient's recent The patient's recent lab results indicate that urine is alkalized (pH=7). The patient is currently taking Chlorpropamide (a weak acid drug and its pKa is about 5). Under this physiological condition, which of the following statements is correct? (You can use the below equation if needed)

A: most chlorpropamide metabolites will be excreted via urine.

B: under this condition, the dosing interval of chlorpropamide should be shorter than usual.

C: most chlorpropamide metabolites will be biologically active.

D: the half-life of chlorpropamide will be increased.

E: a and b

E

Benzylpenicillin is Benzylpenicillin is an example of a weak acid. The pharmacokinetic calculations indicate that the glomerular filtration rate is 100 ml/min, and the free drug plasma concentration is 15 mg/L. What is the drug filtration rate (mg/min)?

A: 0.15

B: 1.5

C: 15

D: 150

E: 1500

B

A patient is taking warfarin with rifampin, a potent CYP450 inducer. What effect will rifampin have on warfarin levels?

A: Increase warfarin levels, leading to bleeding risk

B: Decrease warfarin levels, leading to reduced anticoagulation

C: No change in warfarin levels

D: Warfarin will become a prodrug

E: all of the above

B

Binding of drugs to plasma protein is irreversible

True

False

False

Vaginal creams and gels must be sterile to protect the patient's natural microflora.

True

False

False

The density of hair follicles at the site of application of a transdermal patch is an important factor affecting the rate of absorption of most drugs.

True

False

False

Drug administered as a troche is only absorbed through the buccal and sublingual mucosa and not in the GI tract.

True

False

False

Blood is heavily buffered at pH 7.4

True

False

True

A modified release dosage form designed to avoid drug release in the stomach is known as

A: Delayed release

B: Extended release

C: Controlled release

D: Immediate release

A

Which of the following factors, as described by the Noyes-Whitney equation, would increase the dissolution rate of a drug in a solid oral dosage form?

A: Decreasing the surface area of the drug particles

B: Reducing the diffusion coefficient

C: Increasing the thickness of the diffusion layer

D: Increasing the solubility of the drug

D

Drugs absorbed in the rectum avoid first-pass metabolism

A: True

B: False

C: It depends on whether the drug is hydrophilic or hydrophobic

D: It depends on where in the rectum the drug is absorbed

D

Which of the following are advantages and disadvantages of using liposomes as drug delivery systems?

A: advantage: liposomes are inexpensive to produce. disadvantage: they have limited ability to encapsulate hydrophobic drugs

B: advantage: liposomes can improve drug solubility and stability. disadvantage: they have limited circulation time and potential for rapid clearance by the reticuloendothelial system

C: advantage: liposomes provide long-term drug release without toxicity. disadvantage: they cannot encapsulate hydrophobic drugs

D: advantage: liposomes are easy to administer orally. disadvantage they have no potential for controlled drug release

B

An excipient present in a conventional dosing tablet dosage form that prevents the tablet from sticking to the die following compaction is known as a

A: diluent

B: lubricant

C: unbinder

D: glidant

B

Drug XX has the following relationship between temperature and the rate of first-order drug degradation. Determine the shelf-life at 25°C.

A: 0.018 seconds

B: 175 minutes

C: 29.17 hours

D: 8.86 hours

E: 86.81 hours

C