NUR 210 Principles Of Pharmacology Exam 4 | 70
Verified Questions And Answers With Rationales
| 2026/2027 Updates
Question 1.
A pregnant patient at 28 weeks gestation is prescribed methyldopa for gestational
hypertension. The nurse understands that methyldopa is preferred in pregnancy
because:
• A. It has a long-established safety profile in pregnancy and is a central alpha-2
agonist that reduces sympathetic outflow
• B. It is an ACE inhibitor with proven fetal safety
• C. It is an angiotensin receptor blocker with minimal placental transfer
• D. It is a diuretic that reduces plasma volume without affecting the fetus
Correct Answer: A
Rationale: Methyldopa is the preferred antihypertensive in pregnancy due to its long track
record of safety for both mother and fetus. It is a central alpha-2 agonist that reduces
sympathetic outflow, decreasing blood pressure. ACE inhibitors and ARBs are
contraindicated in pregnancy (Category D/X) due to fetal renal toxicity, oligohydramnios,
and skull hypoplasia. Labetalol and nifedipine are also commonly used in pregnancy.
Diuretics are generally avoided due to reduced placental perfusion.
Question 2.
A pediatric patient weighing 15 kg is prescribed amoxicillin 40 mg/kg/day divided
into three doses. The nurse calculates that each dose should be:
• A. 200 mg per dose
• B. 100 mg per dose
• C. 300 mg per dose
• D. 600 mg per dose
Correct Answer: A
Rationale: Calculation: 40 mg/kg/day × 15 kg = 600 mg/day. Divided into 3 doses: 600 mg
÷ 3 = 200 mg per dose. Pediatric dosing requires careful weight-based calculations and
verification by a second nurse. Amoxicillin is commonly used for otitis media, streptococcal
pharyngitis, and community-acquired pneumonia in children. The suspension form (125
mg/5 mL or 250 mg/5 mL) is typically used for young children.
,Question 3.
A patient in labor is receiving oxytocin for induction. The nurse notes uterine
tachysystole (more than 5 contractions in 10 minutes) with fetal heart rate
decelerations. The priority nursing intervention is:
• A. Decrease or discontinue the oxytocin infusion, reposition the patient, and
administer oxygen
• B. Increase the oxytocin infusion rate to strengthen contractions
• C. Administer a tocolytic to stop all uterine activity immediately
• D. Prepare for emergency cesarean section without further assessment
Correct Answer: A
Rationale: Uterine tachysystole with fetal heart rate decelerations indicates fetal
compromise due to reduced uteroplacental perfusion. The priority is to decrease or
discontinue the oxytocin infusion (which stimulates uterine contractions), reposition the
mother (typically left lateral to improve venous return and placental perfusion), and
administer oxygen via face mask at 10 L/min. If decelerations persist, terbutaline may be
given as a tocolytic. Oxytocin is a high-alert medication requiring continuous fetal
monitoring during administration.
Question 4.
A patient with a known penicillin allergy develops an anaphylactic reaction after
receiving a cephalosporin. The nurse understands that the cross-reactivity between
penicillin and cephalosporins is primarily due to:
• A. Similar beta-lactam ring structure, though the risk is lower than historically
believed (approximately 1-2%)
• B. Identical side chain structures in all penicillins and cephalosporins
• C. Shared mechanism of action inhibiting bacterial cell wall synthesis
• D. Cross-reactivity is a myth; there is no risk of allergic reaction between these drug
classes
Correct Answer: A
Rationale: The beta-lactam ring is structurally similar between penicillins and
cephalosporins, leading to potential cross-reactivity. However, the actual risk is much lower
than historically taught (approximately 1-2% for first-generation cephalosporins, lower for
later generations). Cross-reactivity is higher when cephalosporins share similar R1 side
chains with the specific penicillin. Patients with a history of anaphylaxis to penicillin should
,avoid cephalosporins with similar side chains. A detailed allergy history and possible skin
testing may guide safe antibiotic selection.
Question 5.
A patient with postoperative nausea and vomiting is prescribed promethazine. The
nurse should be aware that promethazine carries which FDA black box warning?
• A. Severe tissue injury, including gangrene, can occur with intravenous
administration due to extravasation
• B. Risk of sudden cardiac death in patients under 18 years of age
• C. Risk of suicidal ideation in all age groups
• D. Risk of severe hepatotoxicity requiring liver transplantation
Correct Answer: A
Rationale: Promethazine carries an FDA black box warning for severe tissue injury,
including gangrene, requiring amputation, when administered by intravenous or
subcutaneous routes due to the risk of severe arterial spasm and extravasation. The
preferred route is deep intramuscular injection. If IV administration is absolutely necessary,
it should be given in a large-bore vein with extreme caution. Promethazine is a
phenothiazine with antihistamine, antiemetic, and sedative properties. It also causes
significant sedation and has fall risk in older adults.
Question 6.
A patient with a severe asthma exacerbation is prescribed magnesium sulfate
intravenously. The nurse understands that magnesium sulfate works in acute asthma
by:
• A. Promoting bronchodilation through smooth muscle relaxation by antagonizing
calcium and reducing acetylcholine release
• B. Stimulating beta-2 receptors directly to cause rapid bronchodilation
• C. Suppressing the immune response and reducing airway inflammation
• D. Inhibiting leukotriene synthesis to prevent bronchoconstriction
Correct Answer: A
Rationale: Magnesium sulfate is a calcium antagonist that promotes smooth muscle
relaxation in the bronchial tree by competing with calcium for binding sites and reducing
acetylcholine release at neuromuscular junctions. It is used as an adjunct in severe asthma
exacerbations unresponsive to standard therapy (beta-agonists, corticosteroids, oxygen).
The typical dose is 2 g IV over 20 minutes. The nurse should monitor for hypotension,
, flushing, and magnesium toxicity (loss of deep tendon reflexes, respiratory depression,
cardiac arrest) in patients with renal impairment.
Question 7.
A patient with opioid use disorder is started on buprenorphine/naloxone (Suboxone)
therapy. The nurse understands that the naloxone component is included to:
• A. Prevent abuse by injection; naloxone is inactive sublingually but blocks opioid
effects if injected intravenously
• B. Enhance the analgesic effect of buprenorphine
• C. Treat concurrent alcohol use disorder
• D. Prevent respiratory depression caused by buprenorphine at high doses
Correct Answer: A
Rationale: Buprenorphine/naloxone (Suboxone) combines buprenorphine (a partial mu-
opioid agonist) with naloxone (an opioid antagonist). When taken sublingually as directed,
naloxone has minimal bioavailability and does not interfere with buprenorphine's
therapeutic effect. However, if the tablet is crushed and injected intravenously, naloxone
becomes active and blocks opioid receptors, precipitating withdrawal and discouraging
abuse. Buprenorphine alone (Subutex) is used during pregnancy and in the initial induction
phase.
Question 8.
A patient with preterm labor at 32 weeks gestation is prescribed betamethasone. The
nurse understands that the primary purpose of antenatal corticosteroid
administration is:
• A. To accelerate fetal lung maturation and reduce the incidence and severity of
respiratory distress syndrome
• B. To stop uterine contractions and delay delivery indefinitely
• C. To treat maternal gestational diabetes by reducing insulin resistance
• D. To prevent maternal infection during the preterm delivery process
Correct Answer: A
Rationale: Antenatal corticosteroids (betamethasone or dexamethasone) are given to
pregnant patients between 24 and 34 weeks gestation (and up to 36+6 weeks in some
guidelines) who are at risk of preterm delivery within 7 days. They cross the placenta and
accelerate fetal lung maturation by stimulating surfactant production in type II
pneumocytes. This reduces the incidence and severity of respiratory distress syndrome
Verified Questions And Answers With Rationales
| 2026/2027 Updates
Question 1.
A pregnant patient at 28 weeks gestation is prescribed methyldopa for gestational
hypertension. The nurse understands that methyldopa is preferred in pregnancy
because:
• A. It has a long-established safety profile in pregnancy and is a central alpha-2
agonist that reduces sympathetic outflow
• B. It is an ACE inhibitor with proven fetal safety
• C. It is an angiotensin receptor blocker with minimal placental transfer
• D. It is a diuretic that reduces plasma volume without affecting the fetus
Correct Answer: A
Rationale: Methyldopa is the preferred antihypertensive in pregnancy due to its long track
record of safety for both mother and fetus. It is a central alpha-2 agonist that reduces
sympathetic outflow, decreasing blood pressure. ACE inhibitors and ARBs are
contraindicated in pregnancy (Category D/X) due to fetal renal toxicity, oligohydramnios,
and skull hypoplasia. Labetalol and nifedipine are also commonly used in pregnancy.
Diuretics are generally avoided due to reduced placental perfusion.
Question 2.
A pediatric patient weighing 15 kg is prescribed amoxicillin 40 mg/kg/day divided
into three doses. The nurse calculates that each dose should be:
• A. 200 mg per dose
• B. 100 mg per dose
• C. 300 mg per dose
• D. 600 mg per dose
Correct Answer: A
Rationale: Calculation: 40 mg/kg/day × 15 kg = 600 mg/day. Divided into 3 doses: 600 mg
÷ 3 = 200 mg per dose. Pediatric dosing requires careful weight-based calculations and
verification by a second nurse. Amoxicillin is commonly used for otitis media, streptococcal
pharyngitis, and community-acquired pneumonia in children. The suspension form (125
mg/5 mL or 250 mg/5 mL) is typically used for young children.
,Question 3.
A patient in labor is receiving oxytocin for induction. The nurse notes uterine
tachysystole (more than 5 contractions in 10 minutes) with fetal heart rate
decelerations. The priority nursing intervention is:
• A. Decrease or discontinue the oxytocin infusion, reposition the patient, and
administer oxygen
• B. Increase the oxytocin infusion rate to strengthen contractions
• C. Administer a tocolytic to stop all uterine activity immediately
• D. Prepare for emergency cesarean section without further assessment
Correct Answer: A
Rationale: Uterine tachysystole with fetal heart rate decelerations indicates fetal
compromise due to reduced uteroplacental perfusion. The priority is to decrease or
discontinue the oxytocin infusion (which stimulates uterine contractions), reposition the
mother (typically left lateral to improve venous return and placental perfusion), and
administer oxygen via face mask at 10 L/min. If decelerations persist, terbutaline may be
given as a tocolytic. Oxytocin is a high-alert medication requiring continuous fetal
monitoring during administration.
Question 4.
A patient with a known penicillin allergy develops an anaphylactic reaction after
receiving a cephalosporin. The nurse understands that the cross-reactivity between
penicillin and cephalosporins is primarily due to:
• A. Similar beta-lactam ring structure, though the risk is lower than historically
believed (approximately 1-2%)
• B. Identical side chain structures in all penicillins and cephalosporins
• C. Shared mechanism of action inhibiting bacterial cell wall synthesis
• D. Cross-reactivity is a myth; there is no risk of allergic reaction between these drug
classes
Correct Answer: A
Rationale: The beta-lactam ring is structurally similar between penicillins and
cephalosporins, leading to potential cross-reactivity. However, the actual risk is much lower
than historically taught (approximately 1-2% for first-generation cephalosporins, lower for
later generations). Cross-reactivity is higher when cephalosporins share similar R1 side
chains with the specific penicillin. Patients with a history of anaphylaxis to penicillin should
,avoid cephalosporins with similar side chains. A detailed allergy history and possible skin
testing may guide safe antibiotic selection.
Question 5.
A patient with postoperative nausea and vomiting is prescribed promethazine. The
nurse should be aware that promethazine carries which FDA black box warning?
• A. Severe tissue injury, including gangrene, can occur with intravenous
administration due to extravasation
• B. Risk of sudden cardiac death in patients under 18 years of age
• C. Risk of suicidal ideation in all age groups
• D. Risk of severe hepatotoxicity requiring liver transplantation
Correct Answer: A
Rationale: Promethazine carries an FDA black box warning for severe tissue injury,
including gangrene, requiring amputation, when administered by intravenous or
subcutaneous routes due to the risk of severe arterial spasm and extravasation. The
preferred route is deep intramuscular injection. If IV administration is absolutely necessary,
it should be given in a large-bore vein with extreme caution. Promethazine is a
phenothiazine with antihistamine, antiemetic, and sedative properties. It also causes
significant sedation and has fall risk in older adults.
Question 6.
A patient with a severe asthma exacerbation is prescribed magnesium sulfate
intravenously. The nurse understands that magnesium sulfate works in acute asthma
by:
• A. Promoting bronchodilation through smooth muscle relaxation by antagonizing
calcium and reducing acetylcholine release
• B. Stimulating beta-2 receptors directly to cause rapid bronchodilation
• C. Suppressing the immune response and reducing airway inflammation
• D. Inhibiting leukotriene synthesis to prevent bronchoconstriction
Correct Answer: A
Rationale: Magnesium sulfate is a calcium antagonist that promotes smooth muscle
relaxation in the bronchial tree by competing with calcium for binding sites and reducing
acetylcholine release at neuromuscular junctions. It is used as an adjunct in severe asthma
exacerbations unresponsive to standard therapy (beta-agonists, corticosteroids, oxygen).
The typical dose is 2 g IV over 20 minutes. The nurse should monitor for hypotension,
, flushing, and magnesium toxicity (loss of deep tendon reflexes, respiratory depression,
cardiac arrest) in patients with renal impairment.
Question 7.
A patient with opioid use disorder is started on buprenorphine/naloxone (Suboxone)
therapy. The nurse understands that the naloxone component is included to:
• A. Prevent abuse by injection; naloxone is inactive sublingually but blocks opioid
effects if injected intravenously
• B. Enhance the analgesic effect of buprenorphine
• C. Treat concurrent alcohol use disorder
• D. Prevent respiratory depression caused by buprenorphine at high doses
Correct Answer: A
Rationale: Buprenorphine/naloxone (Suboxone) combines buprenorphine (a partial mu-
opioid agonist) with naloxone (an opioid antagonist). When taken sublingually as directed,
naloxone has minimal bioavailability and does not interfere with buprenorphine's
therapeutic effect. However, if the tablet is crushed and injected intravenously, naloxone
becomes active and blocks opioid receptors, precipitating withdrawal and discouraging
abuse. Buprenorphine alone (Subutex) is used during pregnancy and in the initial induction
phase.
Question 8.
A patient with preterm labor at 32 weeks gestation is prescribed betamethasone. The
nurse understands that the primary purpose of antenatal corticosteroid
administration is:
• A. To accelerate fetal lung maturation and reduce the incidence and severity of
respiratory distress syndrome
• B. To stop uterine contractions and delay delivery indefinitely
• C. To treat maternal gestational diabetes by reducing insulin resistance
• D. To prevent maternal infection during the preterm delivery process
Correct Answer: A
Rationale: Antenatal corticosteroids (betamethasone or dexamethasone) are given to
pregnant patients between 24 and 34 weeks gestation (and up to 36+6 weeks in some
guidelines) who are at risk of preterm delivery within 7 days. They cross the placenta and
accelerate fetal lung maturation by stimulating surfactant production in type II
pneumocytes. This reduces the incidence and severity of respiratory distress syndrome
