MULTIPLE CHOICE
ANTIMICROBIALS (PHARM 1 EXAM
1) WITH RATIONALES 2026\2027 EXAM GRADED A+
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. - ANSWER: - E. intravenous
The intravenous route of administration is the most desirable because
it results in achievement of therapeutic plasma levels of the antidote
rapidly.
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). - ANSWER: - B. Stomach (pH of 2.5)
Because chlorothiazide is a weakly acidic drug (pKa = 6.5), it will
be predominantly in nonionized form in the stomach (pH of 2.5).
For weak acids, the nonionized form will permeate through cell
membrane readily.
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 aqueous solutions.
D. Chemically unstable drugs.
E. Drugs that are P-glycoprotein substrates. - ANSWER: - C.
Largely hydrophobic, yet soluble in aqueous solutions.
Highly hydrophilic drugs have poor oral bioavailability, because they
are poorly absorbed due to their inability to cross the lipid-rich cell
membranes. Highly lipophilic (hydrophobic) drugs also have poor oral
bioavailability, because they are poorly absorbed due their
,insolubility in aqueous stomach fluids and therefore cannot gain
access to the surface of cells. Therefore, drugs that are largely
hydrophobic, yet have aqueous solubility have greater oral
bioavailability because they are readily absorbed.
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. - ANSWER: - D. Lipid-soluble drugs readily
cross the blood-brain barrier.
Lipid-soluble drugs readily cross the blood-brain barrier because they
can dissolve easily in the membrane of endothelial cells. Ionized or
polar drugs generally fail to cross the blood-brain barrier because
they are unable to pass through the endothelial cells, which do not
have slit junctions. 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. - ANSWER: - A. 1L/Kg
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).
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. - ANSWER: - E. Poor CYP2C19
metabolizer.
Clopidogrel is a prodrug, and it is activated by CYP2C19, which is a
cytochrome P450 (CYP450) enzyme. Thus, patients who are poor
ANTIMICROBIALS (PHARM 1 EXAM
1) WITH RATIONALES 2026\2027 EXAM GRADED A+
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. - ANSWER: - E. intravenous
The intravenous route of administration is the most desirable because
it results in achievement of therapeutic plasma levels of the antidote
rapidly.
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). - ANSWER: - B. Stomach (pH of 2.5)
Because chlorothiazide is a weakly acidic drug (pKa = 6.5), it will
be predominantly in nonionized form in the stomach (pH of 2.5).
For weak acids, the nonionized form will permeate through cell
membrane readily.
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 aqueous solutions.
D. Chemically unstable drugs.
E. Drugs that are P-glycoprotein substrates. - ANSWER: - C.
Largely hydrophobic, yet soluble in aqueous solutions.
Highly hydrophilic drugs have poor oral bioavailability, because they
are poorly absorbed due to their inability to cross the lipid-rich cell
membranes. Highly lipophilic (hydrophobic) drugs also have poor oral
bioavailability, because they are poorly absorbed due their
,insolubility in aqueous stomach fluids and therefore cannot gain
access to the surface of cells. Therefore, drugs that are largely
hydrophobic, yet have aqueous solubility have greater oral
bioavailability because they are readily absorbed.
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. - ANSWER: - D. Lipid-soluble drugs readily
cross the blood-brain barrier.
Lipid-soluble drugs readily cross the blood-brain barrier because they
can dissolve easily in the membrane of endothelial cells. Ionized or
polar drugs generally fail to cross the blood-brain barrier because
they are unable to pass through the endothelial cells, which do not
have slit junctions. 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. - ANSWER: - A. 1L/Kg
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).
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. - ANSWER: - E. Poor CYP2C19
metabolizer.
Clopidogrel is a prodrug, and it is activated by CYP2C19, which is a
cytochrome P450 (CYP450) enzyme. Thus, patients who are poor
