Pharm a 01-04_vignettes_&_practice_questions_no_answers

Pharmacokinetics, Clinical Applications of Pharmacokinetics, Pharmacodynamics
Vignettes & Practice Questions
Don’t hesitate to email me: Micky.Marinelli@RosalindFranklin.edu (do NOT use D2L email to contact me)
or to come to my office (room 2.124)
if any of these are unclear.
>
These vignettes and practice questions should help you “work through” sample problems.
We will go over some of these in class, and you can go over the rest on your own.
Answers are not provided in this file. This will give you a chance at solving the questions yourself.
You can print this file (recommended format of 2/page) and work your way through them on your own
or in class as we go through some of them.
If you have trouble finding the answer, you can go to the file “Vignettes & Practice Questions”, which
contains all the answers and the reasoning behind most answers.

# 2
Vignettes in your handouts
Answer: _____, modifying urine pH can help.
Aspirin is a weak acid. So to help its elimination, you want to make urine more _______.
If you make urine more ______, aspirin (a weak acid) becomes more ionized and thus
remains “trapped” into the urine, without being reabsorbed into the blood stream.
To make urine more ______, you can give ___________________.
I.W., a 30-yr old male student, is studying for his pharmacology exam. He has only eaten two bags of
beef jerky in the past day and a half (no time to leave home!) but he constantly drinks plenty of coke and
orange juice. He has a terrible headache, and decides to take some aspirin to alleviate the pain. The
drug does not seem to work too well, so he takes several more pills. He does not realize that, instead of
the usual dosage (325mg/tablet) he is taking the extra-strength formula (500mg/tablet). He ingests a total
of 10 tablets in 3 hours. Soon after, he experiences heart racing, ringing in the ears, nausea, agitation
and confusion. At the hospital he is diagnosed with aspirin overdose.
Q: Given that aspirin is a weak acid with pKa=3.5, could modifying urine pH help I.W. eliminate the drug
faster, and if so, how? (give both theoretical reasons, and practical approach).
><
Now try to graph what would happen to elimination if your drug were a
weak acid or a weak base (see next slide)

# 3
HA H+ A-+
[1]
HA H+ A-+
Cell Membrane
Plasma pH=7.4
Urine pH=4-8
[1]
100 -
-
-
-
-
50 -
-
-
-
-
0
-
-
-
-
-
-
-
-
-
-
-
[PlasmaDrug]
1 2 3 4 5 6
Time (h)
Sodium bicarbonate
(makes urine more basic)
Drug: weak acid
Orange juice
(makes urine more acidic)
100 -
-
-
-
-
50 -
-
-
-
-
0
-
-
-
-
-
-
-
-
-
-
-
[PlasmaDrug]
1 2 3 4 5 6
Time (h)
Sodium bicarbonate
(makes urine more basic)
Drug: weak base
Orange juice
(makes urine more acidic)
B + H+ BH+
[1]
B + H+ BH+
Cell Membrane
Plasma pH=7.4
Urine pH=4-8
[1]
Making urine more basic (with sodium bicarbonate) or more acidic (with orange
juice) will change the manner in which acids and bases are eliminated.
The slope of elimination curves changes when the pH of the urine changes. ><

# 4
Dr. S, a middle aged man, has always suffered of mild hypertension accompanied by fluid retention. He
never paid much attention to it, so he has never taken any medications, despite the discomfort and
bloating caused by the fluid retention. In addition to this, he has an inguinal hernia, that produces
intermittent pain (when he coughs, laughs, goes skating etc…). He takes tylenol (acetaminophen) to
reduce the pain, and only one pill/day is sufficient. He finally decides to see a doctor concerning his
hernia. The doctor immediately detects hypertension, which is confirmed upon a second visit. The doctor
prescribes demadex (a long-lasting sulfonamide), and says that the hernia is of little concern at the
moment. Dr. S starts taking the diuretic, and feels much better, however, every time the hernia bothers
him, he realizes that he can no longer suppress the pain with tylenol.
Q: Did the hernia condition get worse? What could have happened? What should he do?
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# 5
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Cindy, 52-yr-old woman is used to taking midazolam (a benzodiazepine) when she travels abroad. She
claims that it helps us relive the stress of being in a new country and reduces jet-lag-induced insomnia.
Prior to leaving abroad (Italy), she develops a moderate cough, so she goes to the doctor, who detects
mild bronchitis and prescribes erythromycin, to be taken in the event that the cough worsens. For
“safety” reasons, Cindy decides to take the antibiotic all the same, so as to be sure that her symptoms
will not worsen during her trip. Once she reaches Rome, she has a large meal, a couple of glasses of
Chianti, and then takes her midazolam pill. She develops strong hypotension and respiratory depression,
unlike what she has ever experienced before.
Q: How could this have been avoided?

# 6
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Charles a 32-yr-old man weighing 80 kg (for Q1) or 60 kg (for Q2), has received a cardiac drug orally
every day for the past 4 weeks (0.4 mg/day, in tablet form). Recently, symptoms of appreciable toxicity
appeared. Blood tests indicate that plasma concentrations of the drug are 6.4 ng/mL. These levels are in
the toxic range, whereas ideal therapeutic levels are about 1.6 ng/mL. You stop drug treatment for 1 day,
and now [drug]=3.2 ng/mL.
Q1: What new dosing regimen should Charles use; how long will it take to reach the new plateau?
Q1: What if Charles weighed 60 kg?

# 7
Transport of drugs across membranes
Influence of pH
Which drug would you predict would be absorbed most readily
from the stomach (pH 1)?
a. Weak acid
b. Weak base
><
from the intestine (pH 8)?
a. Weak acid
b. Weak base
HA H+ + A-
Acid
HB+ H+ + B
Base
By making the arrows thicker point to the direction of the reaction if you place
an acid or a base in an acidic environment (pH 1 is acidic; you add H+)
an acid or a base in a basic environment (pH 8 is basic; you add OH-)
HA H+ + A-
Acid
HB+ H+ + B
Base
Note, this is not the “typical” type of question I will be asking,
but it helps us “work through” each step that is necessary for
the understanding of the influence of pH on drug absorption

# 8
Influence of pH
a. Strong acid
b. Weak acid
c. Strong base
d. Weak base
><
a. Strong acid
b. Weak acid
c. Strong base
d. Weak base
HA H+ + A-
Weak Acid
HA H+ + A-
Strong Acid
HB+ H+ + B
Strong Base
HB+ H+ + B
Weak Base
By making the arrows thicker point to the
direction of the reaction for strong and weak acids
By making the arrows thicker point to the
direction of the reaction for strong and weak acids
Note, this is not the “typical” type of question I will be
asking, but it helps us “work through” each step that is
necessary for the understanding of the influence of pH on
drug absorption

# 9
Influence of pH
a. Weak acid
b. Very weak acid
c. Weak base
d. Very weak base
><
a. Weak acid
b. Very weak acid
c. Weak base
d. Very weak base
Note, this is not the “typical” type of question I will be asking,
but it helps us “work through” each step that is necessary for
the understanding of the influence of pH on drug absorption

# 10
Influence of pH
a. Weak acid, pKa = 2.0
b. Weak acid, pKa = 3.5
c. Weak base, pKa = 3.0
d. Weak base, pKa = 9.0
e. There would be no difference
HA H+ A-+
HA H+ A-+
Lipid Mucosal Barrier
Plasma pH=7.4
Gastric Juice pH=1
><
Strength
pKa 1
pKa 2
pKa 3
pKa 4
pKa 5
pKa 6
pKa 7
pKa 8
pKa 9
pKa 1
pKa 2
pKa 3
pKa 4
pKa 5
pKa 6
pKa 7
pKa 8
pKa 9
Strength
Weak Acids Weak Bases

# 11
Influence of pH
from an environment of pH 2.0?
a. Weak acid, pKa = 2.0
b. Weak acid, pKa = 3.5
c. Weak base, pKa = 3.0
d. Weak base, pKa = 9.0
HA H+ A-+
HA H+ A-+
Plasma pH=7.4
Gastric Juice pH=2
><
Strength
pKa 1
pKa 2
pKa 3
pKa 4
pKa 5
pKa 6
pKa 7
pKa 8
pKa 9
pKa 1
pKa 2
pKa 3
pKa 4
pKa 5
pKa 6
pKa 7
pKa 8
pKa 9
Strength

# 12
Influence of pH
B + H+ BH+
Plasma pH=7.4
Large Intestine pH=8
from the large intestine (pH 8)?
a. Weak acid, pKa = 4
b. Weak acid, pKa = 8
c. Weak base, pKa = 4
d. Weak base, pKa = 8
B + H+ BH+
><
Strength
pKa 1
pKa 2
pKa 3
pKa 4
pKa 5
pKa 6
pKa 7
pKa 8
pKa 9
pKa 1
pKa 2
pKa 3
pKa 4
pKa 5
pKa 6
pKa 7
pKa 8
pKa 9
Strength

# 13
Influence of pH
Which weakly acidic drug is distributed more readily
from the stomach (pH 1) to the blood (pH 7.4)?
a. Drug A; pKa = 7.2
b. Drug B; pKa = 7.3
c. Drug C; pKa = 7.4
d. Drug D; pKa = 7.5
e. Drug E; pKa = 7.6
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# 14
Influence of pH
from the blood (pH 7.4) to the cerebrospinal fluid (pH 7.2)?
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# 15
Influence of pH
from the cerebrospinal fluid (pH 7.2) to the blood (pH 7.4)?
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# 16
Influence of pH
from the large intestine (pH 8) to the blood (pH 7.4)?
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# 17
Influence of pH
Which weakly basic drug is distributed more readily
from the blood (pH 7.4) to the milk (pH 6.9) of a lactating mother?
><

# 18
Influence of pH
What is the ratio of ionized to unionized drug (I/UI) for a weak acid with pKa of 4.2 in the urine of a patient
treated with sodium bicarbonate (pH of urine = 8.2)?
a. 100:1
b. 1:1000
c. 1:1
d. 10:1
e. 10,000:1
><

# 19
Influence of pH
A nursing mother is taking penicillin V (a weak acid, pKa = 2.4). The pH of her serum is 7.4, and so is the
one of her milk. However, she drinks orange juice, which acidifies her milk to pH 6.4 (quite an unlikely
scenario, but let’s assume it is true).
Will this change in pH modify the retention of penicillin V in the milk and by how much?
a. Facilitate the retention of penicillin V in the milk by a factor of 100,000
b. Facilitate the retention of penicillin V in the milk by a factor of 10,000
c. Facilitate the retention of penicillin V in the milk by a factor of 10
d. Reduce the retention of penicillin V in the milk by a factor of 100,000
e. Reduce the retention of penicillin V in the milk by a factor of 10,000
f. Reduce the retention of penicillin V in the milk by a factor of 10
><

# 20
Influence of pH
><
A drug that is a weak acid is best absorbed in an environment that is:
a. Acidic
b. Basic
A drug that is a weak base is best absorbed in an environment that is:
a. Acidic
b. Basic
Note, this is not the “typical” type of question I will be
asking, but it helps us “work through” each step that is
necessary for the understanding of the influence of pH on
drug absorption
HA H+ + A- HA H+ + A-
Acidic environment Basic environment
HB+HB+ H+ + B H+ + B
Acidic environment Basic environment
an acid (HA) in an acidic (add H+) or basic (add OH-)
a base (B) in an acidic (add H+) or basic (add OH-)

# 21
Influence of pH
Assuming the passive diffusion hypothesis for the passage of drugs across membranes, the
transport of a weakly acidic drug (pKa = 8.5) will be expected to be greater from a medium of:
a. pH 2.5
b. pH 4.5
c. pH 5.5
d. pH 8.5
e. pH 9.5
><

# 22
Influence of pH
Assuming the passive diffusion hypothesis for the passage of drugs across membranes, the
transport of a weakly basic drug (pKa = 8.5) will be expected to be greater from a medium of:
a. pH 4.2
b. pH 5.2
c. pH 6.2
d. pH 8.5
e. pH 9.5
><

# 23
Influence of pH AND l/w partition coefficient
Which of the following weakly acidic drugs is absorbed more readily from the large intestine?
a. Drug A; pKa=6, l/w=1000000000000
b. Drug B; pKa=6, l/w=100
c. Drug C; pKa=7, l/w=1
d. Drug D; pKa=7, l/w=100
e. Drug E; pKa=8, l/w=1
><
Note: this is an “extreme situation”, and it is unlikely to represent the types of questions
you will be getting. However, it helps work-through the rationale behind these types of
questions and prepares you for more “likely scenarios” (see next question).

# 24
The pKa values for three drugs are Drug A: 8.5, Drug B: 7.7, Drug C: 7.5. These drugs are all weak
ACIDS. Their l/w partition coefficients are 0.005, 0.005, and 50 respectively. According to these
properties, which of the following is the likely correct order of rate of absorption from the stomach?
a. Drug A>Drug B>Drug C
b. Drug A=Drug B>Drug C
c. Drug C>Drug B>Drug A
d. Drug C>Drug A>Drug B
e. Drug C>Drug B=Drug A
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# 25
Which of the following weakly acidic drugs is absorbed more readily from the large intestine?
a. Drug A; pKa=9, l/w=1
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# 26
Which of the following weakly basic drugs is absorbed more readily from the large intestine?
a. Drug A; pKa=9, l/w=1
><

# 27
Factors affecting passive transport of drugs
You are developing a new drug, to be applied as transdermal patch. Ideally drug should be:
a. Large lipophilic compound, with low polarity
b. Small lipophilic compound, with high polarity and protein binding
c. Low degree of ionization, small molecular size, high lipophilicity
d. High lipid solubility and lipid/water partition coefficient and high polarity
e. Low lipid/water partition coefficient and low polarity
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# 28
Drug Absorption
Drug X is administered intramuscularly (curve A) or orally (curve B).
Which of the following statements is NOT correct?
a. Curve A shows shorter half life than curve B
b. Curve B shows less bioavailability than curve A
c. For curve B, elimination has started before absorption is complete
d. For curve A, biovailability is high
e. Curve A follows zero order kinetics; curve B follows first order kinetics
Logplasma[Drug]
-
-
-
-
-
-
-
-
Time (min)
-
-
-
-
-
-
-
-
-
A
B
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# 29
Drug Absorption
First pass effect (or first pass metabolism) can be reduced if drugs are:
a. Very lipophilic
b. Very hydrophilic
c. Administered rectally
d. Administered orally
e. Administered in a buffered solution
><

# 30
Drug Absorption
A patient enters the emergency room with severe signs of angina pectoris and clear signs of imminent
myocardial infarction. To prevent full myocardial infarction, you immediately prescribe a sublingual tablet of
nitroglycerin. One of the main reasons for the sublingual vs. oral route of administration in this situation is:
a. To have rapid drug absorption (by sublingual vasculature)
b. To have slow but safe drug absorption, without risking stomach damage
c. To reduce rapid renal and intestinal clearance and increase duration of effect
d. To have prolonged duration of action of the drug
e. To reduce first pass metabolism from the stomach
><

# 31
Drug Distribution
A 50-yr-old woman with atrial fibrillation has been taking 5mg of warfarin daily for the past year. She develops
a urinary tract infection and, instead of visiting the doctor, she decides to take some left-over pills of
ciprofloxacin acid that were previously prescribed to her daughter. Warfarin is an anticoagulant drug that is
97% bound to plasma proteins, and ciprofloxacin is an antibacterial drug that binds 90% to plasma proteins.
Which adverse effect(s) is(are) most likely to occur after one week combined warfarin + ciprofloxacin acid
treatment?
a. Atrial fibrillation
b. Blood clotting in the extremities
c. Hematomas in the extremities and or/hematuria
d. Accelerated recovery from the urinary tract infection
e. No recovery at all from the urinary tract infection
><

# 32
Drug Distribution
A patient with cardiac failure due to a previous myocardial infarction has been taking daily digoxin (a
cardiotonic drug) for the past 2 months. She develops mild bacteria-induced bronchitis. She has previously
suffered of bacteria-induced bronchitis and has been successfully treated with erythromycin (an
aminoglycoside antibiotic). She has some left-over pills from the year before, which she decides to take to
treat the bronchitis. Given that erythromycin inhibits PGP transport, and that digoxin binds to PGP, which of
the following adverse effects are likely to occur?
a. Blurred vision, heart palpitations and nausea
b. Respiratory depression and vomiting
c. Decreased cardiac output, decreased blood pressure and heart rate
d. Increased state of alertness, difficulty to fall asleep
e. Rapid recovery from bronchitis
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# 33
Drug Distribution
A highly lipid soluble drug has been injected into a patient who dies after 10 minutes.
Which of the following tissues/organs will have the least amount of drug recovered?
a. Liver
b. Blood
c. Skin
d. Kidneys
e. Heart
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# 34
Drug Metabolism
Which of the following best describes phase I metabolism?
a. It involves hydrolysis reactions and requires the presence of NADP+
b. It involves hydrolysis reactions and requires the presence of NADPH
c. It involves functionalization reactions, which expose or introduce functional groups
d. Pharmacological activity changes and polarity decreases
e. Always preceded Phase II metabolism
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# 35
Drug Metabolism
Which of the following descriptions best describes phase II metabolism of a drug?
a. It often conjugates endogenous glucuronic acid with the drug or its metabolites
b. It can only occur after phase I metabolism has occurred in the cytosol
c. It occurs on the endoplasmic reticulum or in microsomes and requires cytochrome P450
d. It decreases the hydrophilic properties of drugs, which increases glomerular filtration
e. It often refers to hydrolysis and/or oxidation reactions
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# 36
Drug Metabolism & Excretion
To facilitate sleep induction a young woman has the habit of taking one pill of alprazolam (a short-
acting benzodiazepine, weak acid, pKa = 5.0) prior to going to bed. She realizes that the pill works
well, however she wakes up too early in the morning, and would like to prolong drug effect. Which of
the following things would be more effective?
a. eat food to reduce gastric emptying
b. drink several glasses of water to accelerate gastric emptying
c. drink some wine, to modify drug effect
d. drink grapefruit juice to acidify urine and to reduce drug metabolism
e. exercise to modify metabolism and blood flow
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# 37
Clinical applications of pharmacokinetics
><
A new drug that follows first order kinetics and whose half life is 8h is administered intravenously in a
patient, as a bolus infusion of 320 mg.
Plasma levels of the drug are measured early-on, during the distribution phase (α phase) and then at 8
h, during the elimination phase (β phase).
Complete the graph below by adding what plasma levels would look like at 12h, 16h, 20h, and 24h
[PlasmaDrug(ng/L]
t ½
320
160
80
40
20
0
Time (h)
4 8 12 16 20 24 28
α phase
phase

# 38
><
Patient G is admitted to the emergency room with a severe infection. She requires immediate treatment
with an antibiotic whose half life is 10h and whose therapeutic window is about 20 mg/L. If the clearance
rate for this antibiotic is about 0.693 L/h, what would be an appropriate first dose (loading dose) one
should administer?
a. 20 mg
b. 40 mg
c. 50 mg
d. 200 mg
e. 300 mg

# 39
><
Drug X follows first order kinetics, and its Kel (constant of elimination) is 0.693/h. If this drug is to be
given as constant IV infusion, approximately how long will it take for the drug to reach Css (steady state
plasma concentrations)?
a. 0.7h
b. 1.0h
c. 1.7h
d. 4.7h
e. 6.9h

# 40
><
Toby is a tiny teenager who weighs 35 kg, and takes 10 mg of a drug whose elimination rate follows
zero order kinetics. If Toby’s Ke for this drug=1mg/h, how long will it take for 50% of the drug to be
eliminated?
a. 0.5h
b. 1.0h
c. 2.5h
d. 5.0h
e. 10.0h

# 41
><
Mr. Blue, a 29-year-old man weighing 140 kg and 1.95 m tall (6.4 feet) is admitted to the hospital with
symptoms of arrhythmias. The doctors prescribe immediate intravenous procainamide. The
pharmacokinetic values for procainamide in a 70 kg person are: Vd 100L, CL 40L/h, therapeutic
concentration 5 mg/L.
Which of the following doses would be most appropriate as an initial (loading) dose?
a. 10 mg
b. 50 mg
c. 100 mg
d. 500 mg
e. 1000 mg

# 42
><
Mr. Blue, a 29-year-old man weighing 140 kg and 1.95 m tall (6.4 feet) is admitted to the hospital with
symptoms of arrhythmias. The doctors prescribe immediate intravenous procainamide. The
pharmacokinetic values for procainamide in a 70 kg person are: Vd 100L, CL 40L/h, therapeutic
concentration 5 mg/L.
What constant intravenous infusion rate should be used to maintain the therapeutic concentration?
a. 80 mg/h
b. 100 mg/h
c. 200 mg/h
d. 400 mg/h
e. 800 mg/h

# 43
><
Graham Negative is a very tall individual; he weighs 140kg (given his height he is not overweight).
He is admitted to the hospital with pneumonia. He is treated with an intravenous antibiotic. In this
individual, the clearance rate of the antibiotic is 4 L/h. If you decide to administer the antibiotic every
4h, what would be a good maintenance dose to administer so as to achieve a steady-state
concentration of 4mg/L?
a. 8 mg
b. 16 mg
c. 32 mg
d. 64 mg
e. 128 mg

# 44
><
The plasma level of an antibiotic is to be maintained at 20 µg/mL in a 60 kg patient. The drug is
95% bound to plasma proteins, and is moderately lipid soluble. It has CL = 15mL/min. What rate
of IV infusion is needed to maintain this concentration?
a. 2 mg/hour
b. 6 mg/hour
c. 12 mg/hour
d. 18 mg/hour
e. 30 mg/hour

# 45
><
Dee Vourer is an overweight young lady who weighs 140kg and who tends to eat everything in sight.
She arrives to the emegency room, showing internal and nose bleeding. She claims to have inadvertently
eaten rat poison containing rodenticide the day before. Rodenticide is an anticoagulant that is very lipid-
soluble. Blood levels of rodenticide are 30 mg/L (24h post ingestion). How many mg of rodenticide did
Dee Vourer ingest 24h before? Note that rodenticide follows first-order kinetics with t½ of 12h and with
Vd=4L in normal adults.
a. 60 mg
b. 120 mg
c. 240 mg
d. 480 mg
e. 960 mg

# 46
><
Ann Orexia is a young patient weighing 50Kg. She is treated with drug X, where target blood levels are
20 micrograms/L.
The pharmacokinetics parameters for this drug in this patient are
Vd = 10L/Kg
CL = 1L/h
Half life = 7h
What is a good LOADING for this patient?
A. 10 micrograms
B. 50 micrograms
C. 100 micrograms
D. 500 micrograms
E. 1 milligram
F. 5 milligrams

# 47
><
Ann Orexia is a young patient weighing 50Kg. She is treated with drug X, where target blood levels are
20 micrograms/L.
The pharmacokinetics parameters for this drug in this patient are
Vd = 10L/Kg
CL = 1L/h
Half life = 7h
What is a good MAINTENANCE dose ONCE DAILY for this patient?
A. 20 micrograms
B. 24 micrograms
C. 48 micrograms
D. 240 micrograms
E. 480 micrograms
F. 2000 micrograms

# 48
><
In the patient above, you stop treatment and then measure blood [drug] after 11.5 min and find that they are
2.5 mg/L. What is the approximate Vd in this patient?
a. 1L
b. 10L
c. 36L
d. 69L
e. It cannot be calculated given the information above
A patient is administered a continuous drug infusion of 3 mg/min for 70 min. Steady-state blood concentration
of the drug are reached by 50 min and are 5 mg/L. The CL rate of this drug is about:
a. 3 mL/min
b. 60 mL/min
c. 600mL/min
d. 900 mL/min
e. 1000 mL/min
If steady state concentrations were reached within 35 min, rather than 50, the clearance rate of this
drug would be about:
What would be a good loading dose?
a. 6 mg
b. 9 mg
c. 25 mg
d. 38 mg
e. 50 mg

# 49
><
Time (hours)
0 4 8 12 16 20 24 28 32 36 40
PlasmaConcentration(mg/L)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
1
0.8
a. CL=2 L/h
b. Vd=30 L
c. T ½ = 4 h
d. Css=0.8 mg/L
e. Elimination follows zero order kinetics
You are developing a new drug for the treatment of breast cancer. Volunteer women are administered the
drug intravenously at the rate of 8mg/h. Given the information collected you can conclude that:

# 50
><
The plasma conc. of an oral hypoglycemic drug is 20 mg/100mL when measured at 2h after
administration. If disposition of drug is assumed to obey first order kinetics (Ke=0.115/h) what will be the
plasma conc. 20h after administration?
a. 5 mg/100mL
b. 4.0 mg/100mL
c. 3.5 mg/100mL
d. 2.5 mg/100mL
e. 2.0 mg/100mL
If you assume that the above drug were to follow zero order kinetics (elimination constant of 1 mg/h)
what will be the plasma conc. At 20h after administration?
a. 5 mg/100mL
b. 4.0 mg/100mL
c. 3.5 mg/100mL
d. 2.5 mg/100mL
e. 2.0 mg/100mL

# 51
><
If 50% of a drug is eliminated by 1h, what is the half life of this drug?
(Assume there is no first-pass effect).
a. 15 min
b. 25 min
c. 30 min
d. 45 min
e. 60 min
f. 120 min

# 52
><
If 50% of a drug is absorbed by 1h, what is the half life of this drug?
a. 15 min
b. 25 min
c. 30 min
d. 45 min
e. 60 min
f. 120 min

# 53
><
If ~88% of a drug is eliminated by 3h, what is the half life of this drug?
a. 15 min
b. 25 min
c. 30 min
d. 45 min
e. 60 min
f. 120 min

# 54
><
If ~88% of a drug is absorbed by 3h, what is the half life of this drug?
a. 15 min
b. 25 min
c. 30 min
d. 45 min
e. 60 min
f. 120 min

# 55
><
A patient (70 kg) is to be administered an experimental drug. Its pharmacokinetic properties are the
following: pKa=3.4, Vd=140L, bioavailability=100%, protein binding=85%, Ke=0.3/hour.
What should be the orally administered loading dose in order to achieve plasma concentrations of 21µg/L?
a. 1.45 mg
b. 2.94 mg
c. 3.94 mg
d. 5.50 mg
e. 7.25 mg

# 56
><
Time (h)
plasmadrugconc(mg/L)
32 -
-
16 -
-
8 -
-
4 -
-
2 -
-
1 -
I I I I I I I I I I I I I I I I I
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
If you are given a graph like the one below, and you are given the loading IV dose, how do you calculate
Vd, CL, and t½?
During the α phase (red circles) the drug concentration in the blood is very high
because the drug has not yet distributed, even though clearance already begun. During the β
phase (black circles) the drug has distributed and clearance is still ongoing.
sodium bicarbonate

# 57
><
The clearance for drug X prior to sodium bicarbonate administration is approximately:
a. 0.7 L/h
b. 1.0 L/h
c. 1.4 L/h
d. 3.5 L/h
e. 7.0 L/h
A new anti-inflammatory drug X is developed and the efficacy and pharmacokinetics are being studied.
The drug is administered to healthy male subjects weighing approximately 70 kg. A dose of 480 mg is
administered intravenously as a bolus infusion and blood samples are analyzed at the time points shown
below (both before and after administration of sodium bicarbonate).
Time (h)
32 -
-
16 -
-
8 -
-
4 -
-
2 -
-
1 -
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
sodium bicarbonate

# 58
><
The clearance for drug X after to sodium bicarbonate administration is approximately:
a. 0.7 L/h
b. 1.0 L/h
c. 1.4 L/h
d. 3.5 L/h
e. 7.0 L/h
A new anti-inflammatory drug X is developed and the efficacy and pharmacokinetics are being studied.
The drug is administered to healthy male subjects weighing approximately 70 kg. A dose of 480 mg is
administered intravenously as a bolus infusion and blood samples are analyzed at the time points shown
below (both before and after administration of sodium bicarbonate).
Time (h)
32 -
-
16 -
-
8 -
-
4 -
-
2 -
-
1 -
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
sodium bicarbonate

# 59
>
Time (h)
0 1 2 3 4 5 6 7 8 9 10 11 12
Plasmaconcentration(mg/L)
2048
1024
512
256
128
64
32
16
8
4
2
1
Cranberry juice
The figure below represents the plasma concentrations of pharmagood, a new drug developed to promote
critical thinking. Pharmagood is given as a bolus intravenous injection of 1024mg in a normal individual (a
pharmacology student, weighing 70kg). The empty circles represent plasma concentrations of pharmagood in
its alpha phase, whereas the filled circles represents concentrations of pharmagood during its beta phase
(before or after the administration of cranberry juice). What is the approximate clearance rate after
the administration of cranberry juice?
a. 0.1 L/h
b. 0.35 L/h
c. 0.7 L/h
d. 1.4 L/h
e. 2.8 L/h
<

# 60
Pharmacodynamics
><
Mr. Pink agrees to pet-sit his neighbor’s cat for a few days. The morning after having spent the night
with the cat, Mr. Pink starts showing signs of mild allergy-induced asthma. He decides to take a tablet
of diphenydramine (benadryl), which causes slight drowsiness, but eventually relieves Mr. Pink from
the allergy-induced discomfort. The second morning, the allergy-induced asthma becomes so severe
that Mr. Pink is required to visit the emergency room for immediate relief of severe asthma. Given the
choice between administering an inhalant preparation of norepinephrine or of beclomethasone (B: a
glucocorticoid, steroid drug), the doctors will opt for norepinephrine because:
a. B will interact with diphenydramine and provoke severe drowsiness
b. B would take too long to have an effect, because it acts on intracellular receptors
c. B’s effects would only last a very short time, b/c benadryl increases its metabolism
d. B cannot be absorbed in inhalant form because it is not lipophilic enough
e. B risks being absorbed in the circulation because it is too lipophilic

# 61
Pharmacodynamics
><
Which of the following is true about metabotropic receptors?
a. When activated, they metabolize drugs
b. When activated, they phosphorylate a protein kinase
c. They are associated to G proteins
d. They are associated to excitatory G proteins
e. They need to translocate into the nucleus to have an effect

# 62
Pharmacodynamics
><
In the figure below, drugs X, Y and Z have been developed to reduce pharmacology-associated headaches. All
three drugs act on a new receptor (pharmidache).
Which of the following is true?
a. Drug Z is a partial agonist with high affinity for pharmidache receptors
b. Drug Z is a full agonist with high affinity for pharmidache receptors
c. Drug Z is a full agonist with low affinity for pharmidache receptors
d. Drug Y is a partial agonist with high affinity for pharmidache receptors
e. Drug Y is a full agonist with low affinity for pharmidache receptors
100 -
-
-
-
-
50 -
-
-
-
-
0
%ofmaximalresponse
-
-
-
-
1 10 100 1000
-
-
-
-
1 10 100 1000
Log [Drug]
X
Y
Z

# 63
Pharmacodynamics
><
In the figure below, the graded dose-response curve for a drug is presented for the drug alone (Drug A) and
in combination with other drugs (A+B, A+C, A+D).
If Drug A is highly bound to plasma proteins, which drug may have displaced Drug A from its protein binding
sites on the plasma proteins?
a. Drug B
b. Drug C
c. Drug D
d. Drug B and C
e. Drug C and D

# 64
Pharmacodynamics
><
In the figure below, the graded dose-response curve for a drug is presented for the drug alone (Drug A) and in
combination with other drugs (A+B, A+C, A+D). What is drug D?
a. It is a non-equilibrium antagonist, which decreases the potency of Drug A
b. It is a non-equilibrium antagonist, which decreases the efficacy of Drug A
c. It is an equilibrium antagonist, which decreases the potency of Drug A
d. It is an equilibrium antagonist, which decreases the efficacy of Drug A
e. It is a non-competitive antagonist, which decreases the efficacy of Drug A

# 65
Pharmacodynamics
><Dose (mg)
0 1 10 100 1000 10000
%MaxiumumResponse
10
20
30
40
50
60
70
80
90
100
Patient 1
Patient 2
Patient 3
Based on the graph, which of the following statements is true?
(solid lines=therapeutic effect; dotted lines=tachycardia side-effect; max side effect is an increase of 100BPM)
a. At the therapeutic ED50 nobody would experience more than a very slight tachycardia
b. At the therapeutic ED50 one of the individuals would show moderate (+25BPM) tachycardia
c. At the therapeutic ED99 one individual would definitely have major tachycardia (at least +75BPM)
d. At the therapeutic ED99 two patients would reveal an increase in heart rate

# 66
Pharmacodynamics
<
Dose (mg)
0 1 10 100 1000 10000
%MaxiumumResponse
10
20
30
40
50
60
70
80
90
100
Blood pressure reduction
(max effect: 40mm/Hg)
Increase in heart rate (tachycardia)
(max effect: 1 beat/min)
Impotence
(max effect: 100% impotence)
Ankle swelling
(max effect: 1mm)
a. Tachycardia, impotence, ankle swelling
b. Tachycardia and impotence
c. Impotence and ankle swelling
d. Tachycardia
e. Impotence
In this figure, the graded dose-response curves represent the effects and side-effects of a novel vasodilator
designed as anti-hypertensive medication. For it to be more effective than simple change in life-style, it needs
to be administered at the EC90. Eager to try the new drug, you administer it to a set of male patients (ages 25-
40). After a week of treatment, all patients return to your office; they report to be uncomfortable with the side
effect(s) they are experiencing. What are they most-likely complaining about?
(NOTE: Read the graph carefully, including
all the words in the legend. Use your judgment
to determine if each side-effect, at the
degree it is experienced, would cause
discomfort or not).

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