NURS 251 | Pharmacology Module 10 2026/2027 Exam
NURS 251 Pharmacology Module 10 Exam
Endocrine System Pharmacology —
Portage Learning · ABC Nursing · Geneva College
Questions and Verified Answers, 100% Guarantee Pass
Comprehensive coverage of endocrine pharmacology: hormonal regulation, insulin and antidiabetic
agents, thyroid and parathyroid pharmacology, corticosteroids, reproductive hormones, osteoporosis
therapy, and endocrine nursing safety and monitoring.
Exam Composition: 70% scenario-based clinical application · 30% direct recall of classifications, mechanisms,
and monitoring parameters · Cognitive levels: 35% recall / 45% application / 20% analysis · Each question
includes verified answer, endocrine pharmacology-specific rationale, and nursing application notes.
Section 1: Endocrine System Pharmacology Foundations
Hormonal Regulation, Feedback Loops, & Drug Principles (Q1-Q12)
Q1: A nurse is explaining the concept of negative feedback in endocrine regulation to a
nursing student. Which statement by the student indicates correct understanding?
A. Negative feedback means hormones are secreted continuously without regulation.
B. Negative feedback occurs when the end product of a pathway inhibits the initial hormone
secretion, maintaining homeostasis (e.g., elevated thyroid hormones suppress TSH release).
[CORRECT]
C. Negative feedback refers to the patient experiencing adverse effects from medication.
D. Negative feedback only occurs in the parathyroid gland.
Correct Answer: B
Rationale: Negative feedback is the primary regulatory mechanism in endocrine function: the end
product of a hormonal pathway inhibits further release of the upstream hormone. For example, elevated
circulating thyroid hormones (T3/T4) inhibit TRH from the hypothalamus and TSH from the pituitary,
maintaining homeostasis. Options A, C, and D misrepresent this physiologic principle. Understanding
feedback is critical for interpreting lab results during hormone replacement therapy.
Q2: Which structure is the master regulator of the endocrine system, integrating signals
from the nervous system and controlling pituitary function?
A. Adrenal medulla
B. Hypothalamus [CORRECT]
C. Thyroid gland
D. Pancreas
Correct Answer: B
Rationale: The hypothalamus is the master regulator of the endocrine system, releasing releasing and
inhibiting hormones (e.g., TRH, CRH, GnRH, GHRH, somatostatin, dopamine) that control the anterior
pituitary. It also produces ADH and oxytocin, stored in the posterior pituitary. The adrenal medulla (A)
releases catecholamines; the thyroid (C) regulates metabolism; the pancreas (D) regulates glucose.
Page 1 | 90 Questions | Portage Learning / ABC Nursing / Geneva College
,NURS 251 | Pharmacology Module 10 2026/2027 Exam
Q3: Which type of hormone receptor mechanism allows the hormone-receptor complex to
directly alter gene transcription in the target cell?
A. G-protein coupled receptors on the cell surface.
B. Intracellular (nuclear or cytoplasmic) receptors that bind lipophilic hormones (e.g.,
steroids, thyroid hormone) and alter gene transcription. [CORRECT]
C. Ion channel-linked receptors only.
D. Tyrosine kinase receptors on the cell membrane.
Correct Answer: B
Rationale: Lipophilic hormones (steroids such as cortisol, estrogens, androgens; and thyroid hormones)
cross the cell membrane and bind intracellular receptors. The hormone-receptor complex then
translocates to the nucleus and directly alters gene transcription. Water-soluble hormones (peptides,
catecholamines) use cell-surface receptors (G-protein coupled, tyrosine kinase, or ion channel-linked)
and act via second messengers.
Q4: A patient is receiving a hormone medication that works via a cell-surface G-protein
coupled receptor. Which hormone medication is MOST likely being administered?
A. Levothyroxine (T4)
B. Prednisone (corticosteroid)
C. Insulin (peptide) [CORRECT]
D. Estradiol (estrogen)
Correct Answer: C
Rationale: Insulin is a peptide hormone that binds cell-surface tyrosine kinase receptors (a related
mechanism to GPCRs in that it does not cross the cell membrane). Levothyroxine (A), prednisone (B), and
estradiol (D) are lipophilic hormones that cross the cell membrane and bind intracellular receptors,
acting via genomic mechanisms. Water-soluble hormones (peptides, catecholamines) act via cell-surface
receptors and second messengers.
Q5: A patient taking an oral corticosteroid develops iatrogenic Cushing's syndrome. Which
endocrine principle BEST explains this adverse effect?
A. Positive feedback from exogenous steroids.
B. Negative feedback suppression of the HPA axis by exogenous glucocorticoids, causing
decreased CRH, ACTH, and endogenous cortisol, with exogenous steroid effects dominating.
[CORRECT]
C. Autoimmune destruction of the adrenal cortex.
D. Increased conversion of T4 to T3.
Correct Answer: B
Rationale: Exogenous corticosteroids suppress the hypothalamic-pituitary-adrenal (HPA) axis via
negative feedback: they inhibit CRH and ACTH secretion, leading to adrenal atrophy and decreased
endogenous cortisol. Prolonged use causes iatrogenic Cushing's syndrome. Abrupt discontinuation can
precipitate adrenal crisis due to suppressed adrenal function. This principle underlies corticosteroid
tapering protocols.
Page 2 | 90 Questions | Portage Learning / ABC Nursing / Geneva College
,NURS 251 | Pharmacology Module 10 2026/2027 Exam
Q6: A patient asks why thyroid hormone levels (TSH, free T4) must be monitored
periodically while taking levothyroxine. The nurse's BEST response is based on which
pharmacologic principle?
A. Levothyroxine has a narrow therapeutic window and accumulates rapidly, requiring frequent
dose adjustment.
B. Levothyroxine replaces endogenous T4, and the dose must be titrated based on TSH
(negative feedback marker) to maintain euthyroid status without causing hyperthyroidism.
[CORRECT]
C. Levothyroxine directly stimulates TSH release.
D. Levothyroxine interacts with all other medications, requiring constant monitoring.
Correct Answer: B
Rationale: Levothyroxine is thyroid hormone replacement; TSH is the most sensitive marker of thyroid
hormone status (negative feedback). Dose is titrated to maintain TSH within the reference range. Too
much levothyroxine suppresses TSH (iatrogenic hyperthyroidism); too little elevates TSH (persistent
hypothyroidism). Monitoring TSH 6-8 weeks after dose changes is standard practice.
Q7: A nurse is preparing to administer a hormone medication. The drug has a long half-life,
lipophilic properties, and acts via intracellular receptors. Which of the following is MOST
likely to have this pharmacokinetic profile?
A. Insulin
B. Levothyroxine [CORRECT]
C. Furosemide
D. Warfarin
Correct Answer: B
Rationale: Levothyroxine (T4) is a lipophilic, slow-acting hormone with a half-life of approximately 7
days; it crosses cell membranes and binds intracellular receptors that alter gene transcription. Insulin is
water-soluble with a short half-life (minutes). Furosemide and warfarin are not hormones. The long
half-life of T4 allows once-daily dosing and explains why TSH monitoring is done 6-8 weeks after dose
changes.
Q8: A patient is receiving vasopressin for diabetes insipidus. The nurse understands that
vasopressin acts primarily on which target organ to regulate water balance?
A. Heart
B. Kidney (collecting duct) [CORRECT]
C. Liver
D. Lungs
Correct Answer: B
Rationale: Vasopressin (ADH) acts on V2 receptors in the renal collecting duct, increasing water
permeability via aquaporin-2 channels and promoting water reabsorption. This concentrates urine and
reduces urine output. In diabetes insipidus (deficient ADH), vasopressin replacement restores water
balance. The heart, liver, and lungs are not primary targets for ADH's antidiuretic effect.
Page 3 | 90 Questions | Portage Learning / ABC Nursing / Geneva College
, NURS 251 | Pharmacology Module 10 2026/2027 Exam
Q9: Which laboratory value is the MOST accurate indicator of long-term glycemic control in
a patient with diabetes mellitus?
A. Fasting blood glucose
B. Hemoglobin A1c (HbA1c) [CORRECT]
C. Random glucose
D. Urine ketones
Correct Answer: B
Rationale: Hemoglobin A1c (HbA1c) reflects average blood glucose over the previous 2-3 months (the
lifespan of hemoglobin A), providing an accurate marker of long-term glycemic control. The American
Diabetes Association target is typically <7% for most adults. Fasting/random glucose reflect momentary
values; urine ketones indicate ketone production, not chronic glycemic control. HbA1c is checked every
3-6 months.
Q10: A nurse is teaching a patient about the importance of medication adherence with
levothyroxine. The patient asks why it must be taken lifelong. The BEST response is based
on which endocrine principle?
A. Levothyroxine cures hypothyroidism after 6 months of therapy.
B. Primary hypothyroidism results in permanent loss of endogenous thyroid hormone
production, requiring lifelong replacement therapy to maintain euthyroid status.
[CORRECT]
C. Levothyroxine acts as a temporary stimulant for the thyroid gland.
D. Hypothyroidism resolves spontaneously with dietary changes.
Correct Answer: B
Rationale: Primary hypothyroidism (e.g., Hashimoto's thyroiditis, post-thyroidectomy, radioactive iodine
therapy) results in permanent loss of thyroid hormone production, requiring lifelong replacement with
levothyroxine. The medication does not cure the underlying condition; it replaces the missing hormone.
Patient education on lifelong adherence and routine TSH monitoring is essential.
Q11: Which endocrine medication acts by inhibiting an enzyme involved in hormone
synthesis rather than replacing a hormone?
A. Levothyroxine for hypothyroidism.
B. Methimazole for hyperthyroidism (inhibits thyroid peroxidase, blocking iodine
organification and coupling). [CORRECT]
C. Insulin for type 1 diabetes.
D. Hydrocortisone for adrenal insufficiency.
Correct Answer: B
Rationale: Methimazole inhibits thyroid peroxidase, the enzyme responsible for oxidation of iodide,
organification of tyrosine, and coupling of MIT/DIT to form T3 and T4. This reduces endogenous thyroid
hormone synthesis. Levothyroxine, insulin, and hydrocortisone are replacement therapies. PTU
(propylthiouracil) also inhibits peripheral T4-to-T3 conversion, but methimazole is preferred except in the
first trimester of pregnancy.
Page 4 | 90 Questions | Portage Learning / ABC Nursing / Geneva College
NURS 251 Pharmacology Module 10 Exam
Endocrine System Pharmacology —
Portage Learning · ABC Nursing · Geneva College
Questions and Verified Answers, 100% Guarantee Pass
Comprehensive coverage of endocrine pharmacology: hormonal regulation, insulin and antidiabetic
agents, thyroid and parathyroid pharmacology, corticosteroids, reproductive hormones, osteoporosis
therapy, and endocrine nursing safety and monitoring.
Exam Composition: 70% scenario-based clinical application · 30% direct recall of classifications, mechanisms,
and monitoring parameters · Cognitive levels: 35% recall / 45% application / 20% analysis · Each question
includes verified answer, endocrine pharmacology-specific rationale, and nursing application notes.
Section 1: Endocrine System Pharmacology Foundations
Hormonal Regulation, Feedback Loops, & Drug Principles (Q1-Q12)
Q1: A nurse is explaining the concept of negative feedback in endocrine regulation to a
nursing student. Which statement by the student indicates correct understanding?
A. Negative feedback means hormones are secreted continuously without regulation.
B. Negative feedback occurs when the end product of a pathway inhibits the initial hormone
secretion, maintaining homeostasis (e.g., elevated thyroid hormones suppress TSH release).
[CORRECT]
C. Negative feedback refers to the patient experiencing adverse effects from medication.
D. Negative feedback only occurs in the parathyroid gland.
Correct Answer: B
Rationale: Negative feedback is the primary regulatory mechanism in endocrine function: the end
product of a hormonal pathway inhibits further release of the upstream hormone. For example, elevated
circulating thyroid hormones (T3/T4) inhibit TRH from the hypothalamus and TSH from the pituitary,
maintaining homeostasis. Options A, C, and D misrepresent this physiologic principle. Understanding
feedback is critical for interpreting lab results during hormone replacement therapy.
Q2: Which structure is the master regulator of the endocrine system, integrating signals
from the nervous system and controlling pituitary function?
A. Adrenal medulla
B. Hypothalamus [CORRECT]
C. Thyroid gland
D. Pancreas
Correct Answer: B
Rationale: The hypothalamus is the master regulator of the endocrine system, releasing releasing and
inhibiting hormones (e.g., TRH, CRH, GnRH, GHRH, somatostatin, dopamine) that control the anterior
pituitary. It also produces ADH and oxytocin, stored in the posterior pituitary. The adrenal medulla (A)
releases catecholamines; the thyroid (C) regulates metabolism; the pancreas (D) regulates glucose.
Page 1 | 90 Questions | Portage Learning / ABC Nursing / Geneva College
,NURS 251 | Pharmacology Module 10 2026/2027 Exam
Q3: Which type of hormone receptor mechanism allows the hormone-receptor complex to
directly alter gene transcription in the target cell?
A. G-protein coupled receptors on the cell surface.
B. Intracellular (nuclear or cytoplasmic) receptors that bind lipophilic hormones (e.g.,
steroids, thyroid hormone) and alter gene transcription. [CORRECT]
C. Ion channel-linked receptors only.
D. Tyrosine kinase receptors on the cell membrane.
Correct Answer: B
Rationale: Lipophilic hormones (steroids such as cortisol, estrogens, androgens; and thyroid hormones)
cross the cell membrane and bind intracellular receptors. The hormone-receptor complex then
translocates to the nucleus and directly alters gene transcription. Water-soluble hormones (peptides,
catecholamines) use cell-surface receptors (G-protein coupled, tyrosine kinase, or ion channel-linked)
and act via second messengers.
Q4: A patient is receiving a hormone medication that works via a cell-surface G-protein
coupled receptor. Which hormone medication is MOST likely being administered?
A. Levothyroxine (T4)
B. Prednisone (corticosteroid)
C. Insulin (peptide) [CORRECT]
D. Estradiol (estrogen)
Correct Answer: C
Rationale: Insulin is a peptide hormone that binds cell-surface tyrosine kinase receptors (a related
mechanism to GPCRs in that it does not cross the cell membrane). Levothyroxine (A), prednisone (B), and
estradiol (D) are lipophilic hormones that cross the cell membrane and bind intracellular receptors,
acting via genomic mechanisms. Water-soluble hormones (peptides, catecholamines) act via cell-surface
receptors and second messengers.
Q5: A patient taking an oral corticosteroid develops iatrogenic Cushing's syndrome. Which
endocrine principle BEST explains this adverse effect?
A. Positive feedback from exogenous steroids.
B. Negative feedback suppression of the HPA axis by exogenous glucocorticoids, causing
decreased CRH, ACTH, and endogenous cortisol, with exogenous steroid effects dominating.
[CORRECT]
C. Autoimmune destruction of the adrenal cortex.
D. Increased conversion of T4 to T3.
Correct Answer: B
Rationale: Exogenous corticosteroids suppress the hypothalamic-pituitary-adrenal (HPA) axis via
negative feedback: they inhibit CRH and ACTH secretion, leading to adrenal atrophy and decreased
endogenous cortisol. Prolonged use causes iatrogenic Cushing's syndrome. Abrupt discontinuation can
precipitate adrenal crisis due to suppressed adrenal function. This principle underlies corticosteroid
tapering protocols.
Page 2 | 90 Questions | Portage Learning / ABC Nursing / Geneva College
,NURS 251 | Pharmacology Module 10 2026/2027 Exam
Q6: A patient asks why thyroid hormone levels (TSH, free T4) must be monitored
periodically while taking levothyroxine. The nurse's BEST response is based on which
pharmacologic principle?
A. Levothyroxine has a narrow therapeutic window and accumulates rapidly, requiring frequent
dose adjustment.
B. Levothyroxine replaces endogenous T4, and the dose must be titrated based on TSH
(negative feedback marker) to maintain euthyroid status without causing hyperthyroidism.
[CORRECT]
C. Levothyroxine directly stimulates TSH release.
D. Levothyroxine interacts with all other medications, requiring constant monitoring.
Correct Answer: B
Rationale: Levothyroxine is thyroid hormone replacement; TSH is the most sensitive marker of thyroid
hormone status (negative feedback). Dose is titrated to maintain TSH within the reference range. Too
much levothyroxine suppresses TSH (iatrogenic hyperthyroidism); too little elevates TSH (persistent
hypothyroidism). Monitoring TSH 6-8 weeks after dose changes is standard practice.
Q7: A nurse is preparing to administer a hormone medication. The drug has a long half-life,
lipophilic properties, and acts via intracellular receptors. Which of the following is MOST
likely to have this pharmacokinetic profile?
A. Insulin
B. Levothyroxine [CORRECT]
C. Furosemide
D. Warfarin
Correct Answer: B
Rationale: Levothyroxine (T4) is a lipophilic, slow-acting hormone with a half-life of approximately 7
days; it crosses cell membranes and binds intracellular receptors that alter gene transcription. Insulin is
water-soluble with a short half-life (minutes). Furosemide and warfarin are not hormones. The long
half-life of T4 allows once-daily dosing and explains why TSH monitoring is done 6-8 weeks after dose
changes.
Q8: A patient is receiving vasopressin for diabetes insipidus. The nurse understands that
vasopressin acts primarily on which target organ to regulate water balance?
A. Heart
B. Kidney (collecting duct) [CORRECT]
C. Liver
D. Lungs
Correct Answer: B
Rationale: Vasopressin (ADH) acts on V2 receptors in the renal collecting duct, increasing water
permeability via aquaporin-2 channels and promoting water reabsorption. This concentrates urine and
reduces urine output. In diabetes insipidus (deficient ADH), vasopressin replacement restores water
balance. The heart, liver, and lungs are not primary targets for ADH's antidiuretic effect.
Page 3 | 90 Questions | Portage Learning / ABC Nursing / Geneva College
, NURS 251 | Pharmacology Module 10 2026/2027 Exam
Q9: Which laboratory value is the MOST accurate indicator of long-term glycemic control in
a patient with diabetes mellitus?
A. Fasting blood glucose
B. Hemoglobin A1c (HbA1c) [CORRECT]
C. Random glucose
D. Urine ketones
Correct Answer: B
Rationale: Hemoglobin A1c (HbA1c) reflects average blood glucose over the previous 2-3 months (the
lifespan of hemoglobin A), providing an accurate marker of long-term glycemic control. The American
Diabetes Association target is typically <7% for most adults. Fasting/random glucose reflect momentary
values; urine ketones indicate ketone production, not chronic glycemic control. HbA1c is checked every
3-6 months.
Q10: A nurse is teaching a patient about the importance of medication adherence with
levothyroxine. The patient asks why it must be taken lifelong. The BEST response is based
on which endocrine principle?
A. Levothyroxine cures hypothyroidism after 6 months of therapy.
B. Primary hypothyroidism results in permanent loss of endogenous thyroid hormone
production, requiring lifelong replacement therapy to maintain euthyroid status.
[CORRECT]
C. Levothyroxine acts as a temporary stimulant for the thyroid gland.
D. Hypothyroidism resolves spontaneously with dietary changes.
Correct Answer: B
Rationale: Primary hypothyroidism (e.g., Hashimoto's thyroiditis, post-thyroidectomy, radioactive iodine
therapy) results in permanent loss of thyroid hormone production, requiring lifelong replacement with
levothyroxine. The medication does not cure the underlying condition; it replaces the missing hormone.
Patient education on lifelong adherence and routine TSH monitoring is essential.
Q11: Which endocrine medication acts by inhibiting an enzyme involved in hormone
synthesis rather than replacing a hormone?
A. Levothyroxine for hypothyroidism.
B. Methimazole for hyperthyroidism (inhibits thyroid peroxidase, blocking iodine
organification and coupling). [CORRECT]
C. Insulin for type 1 diabetes.
D. Hydrocortisone for adrenal insufficiency.
Correct Answer: B
Rationale: Methimazole inhibits thyroid peroxidase, the enzyme responsible for oxidation of iodide,
organification of tyrosine, and coupling of MIT/DIT to form T3 and T4. This reduces endogenous thyroid
hormone synthesis. Levothyroxine, insulin, and hydrocortisone are replacement therapies. PTU
(propylthiouracil) also inhibits peripheral T4-to-T3 conversion, but methimazole is preferred except in the
first trimester of pregnancy.
Page 4 | 90 Questions | Portage Learning / ABC Nursing / Geneva College
