PHM 520 Final Exam Practice Questions
With Verified Answers
What type of reactions are the most common cause of drug incompatibility and why? -
answer✔acid-base reactions because precipitation of nonionized drug forms
approximately how many commonly used drugs are incompatible or unstable when added or
combined with usual fluids or agents?
a. 10%
b. 30%
c. 50%
d. 70% - answer✔b. 30%
an undesirable reaction occurring between a drug and a container, solution, or another drug is
called? - answer✔incompatibility
alteration of drug effect due to the influence of another substance is called? - answer✔drug
interactions
where do interactions occur? - answer✔inside the body
where does incompatibility occur? - answer✔in a fluid contianer or infusion line
are interactions or are incompatibilities visible? - answer✔incompatibilities
what type of incompatibility results from the modification of pharmacological effect from prior
concomitant administration of other drugs? - answer✔therapeutic incompatibilty
what mechanism of therapeutic incompatibility involves the effect of a drug on another from the
point of view of absorption, distribution, metabolism, and excretion? - answer✔pharmacokinetic
what mechanism of therapeutic incompatibility is related to pharmacological activity of the
interacting drugs such as synergism/antagonism? - answer✔pharmacodynamic
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pharmacodynamic is what the _______ does to the _______ - answer✔drug, body
pharmacokinetic is what the _______ does to the ________ - answer✔body, drug
an interaction that results in change in color, odor, taste, viscosity, and morphology is what type
of incompatibility? - answer✔physical incompatibility
physical incompatibilities usually refer to? - answer✔precipitation or phase separation
what are factors responsible for physical incompatibility? - answer✔pH value and buffer
capacity, solubility and precipitation, complex formation, adsorption
what effect will ingestion of antacids over a period of 24 hours have on urinary pH? -
answer✔increase pH
are acidic drugs excreted faster or slower when urinary pH is alkaline? - answer✔faster
acidic drugs will diffuse back into the blood from the urine when the urine is acidic or alkaline? -
answer✔acidic
interactions between ionized drugs will form _______ with _______ charges -
answer✔complexes, reduced
cation-anion interactions result in? - answer✔formation of relatively insoluble precipitate
ion pair formation results in? - answer✔burying of charges
what is the interaction between a metal atom or ion and another species called? -
answer✔chelation
the attachment of a molecule to a surface is called? - answer✔adsorption
what type of incompatibility results in change in chemical properties of pharmaceutical dosage
form? - answer✔chemical incompatibility
hydrolysis, oxidation, reduction, racemization are types of what incompatibility? -
answer✔chemical
which types of solubilization methods use a means of entrapment?
a) complexation
b) micellar
c) hydrotrophy
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d) a and b
e) all of the above - answer✔*d) a and b
which of the following expresses the number of moles of solute in 1 kg of solvent?
a) molarity (M)
b) molality (m)
c) normality (N)
d) mole fraction - answer✔*b) molality (m)
a is incorrect because molarity expresses the number of moles of solute in 1 liter of SOLUTION
c is wrong because it expresses the number of equivalents of solute in 1 liter of solution
d is wrong because it expresses the ratio of moles of constituent to total moles
driving force in drug movement in aqueous diffusion model:
a) active transport
b) facilitated transport
c) concentration gradient
d) all of the above - answer✔*c) concentration gradient
which are most likely to diffuse across membranes:
a) charged drugs
b) ionized drugs
c) polar drugs
d) non-ionized drugs - answer✔*d) non-ionized drugs
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a, b, and c are all hydrophilic and are not as likely to cross the membrane since membrane
permeability favors more lipophilic drugs
which equation describes change in concentration with time at a specific location by taking into
account the cross sectional area and partition coefficient?
a) Fick's first law
b) Fick's second law
c) Noyes-Whitney law
d) angle of repose - answer✔*b) Fick's second law
a is incorrect because Fick's first law describes the amount of drug flowing through a unit area of
barrier in unit time, and doesn't take into account cross sectional area or partition coefficient
c is incorrect because it describes dissolution rate
d is incorrect because it describes flow properties of a powder
which solubilization process involves the use of cyclodextrin, which is an oligosaccharide with a
hydrophobic cavity?
a) complexation
b) hydrotrophy
c) pH adjustment
d) crystal modification - answer✔*a) complexation
b involves adding a large amount of a second solute to increase solubility
c is used to prevent precipitation of drug