LEHNE PHARM INDIRECT-ACTING
ANTIADRENERGIC AGENTS PRACTICE QUESTION
AND ANSWERS 2026-2027 UPDATE EXAM | 100%
VERIFIED CORRECT ANSWERS A+ GRADED.
1. Indirect-acting antiadrenergic agents primarily lower blood pressure by:
A. Blocking β1 receptors directly
B. Blocking α1 receptors directly
C. Reducing sympathetic activity without directly blocking peripheral
adrenergic receptors
D. Increasing parasympathetic activity
Rationale: These drugs reduce adrenergic stimulation indirectly through central
or neuronal mechanisms.
2. Which two major groups comprise indirect-acting antiadrenergic agents?
A. Alpha blockers and beta blockers
B. Centrally acting α2 agonists and adrenergic neuron-blocking agents
C. Cholinergics and anticholinergics
D. Calcium channel blockers and ACE inhibitors
Rationale: Indirect antiadrenergics are classified into centrally acting α2
agonists and neuron-blocking agents.
3. Which drug is a centrally acting α2-adrenergic agonist?
A. Prazosin
B. Phenoxybenzamine
C. Propranolol
D. Clonidine
Rationale: Clonidine lowers blood pressure by stimulating central α2 receptors.
4. Clonidine lowers blood pressure mainly by:
A. Increasing cardiac output
, B. Blocking α1 receptors
C. Reducing sympathetic outflow from the CNS
D. Increasing norepinephrine release
Rationale: Activation of central α2 receptors suppresses sympathetic discharge.
5. The principal receptor involved in the antihypertensive action of clonidine
is:
A. α1
B. β1
C. β2
D. α2
Rationale: Central postsynaptic α2 receptors mediate the antihypertensive
effect.
6. Which drug is considered a prodrug that is converted to α-
methylnorepinephrine?
A. Guanfacine
B. Clonidine
C. Methyldopa
D. Reserpine
Rationale: Methyldopa must be converted in the CNS to its active metabolite.
7. Methyldopa is especially important in treating:
A. Heart failure
B. Migraine
C. ADHD
D. Hypertension during pregnancy
Rationale: Methyldopa has a long history of safe use in pregnancy-associated
hypertension.
8. Which adverse effect is common with clonidine therapy?
A. Hyperactivity
B. Tachycardia
, C. Dry mouth
D. Diarrhea
Rationale: Xerostomia is one of the most common adverse effects.
9. Abrupt discontinuation of clonidine may result in:
A. Severe bradycardia
B. Heart block
C. Hypoglycemia
D. Rebound hypertension
Rationale: Sudden withdrawal can trigger excessive sympathetic activity.
10.Which centrally acting α2 agonist has a longer half-life and less rebound
hypertension than clonidine?
A. Methyldopa
B. Reserpine
C. Guanfacine
D. Prazosin
Rationale: Guanfacine’s longer duration reduces withdrawal-related
hypertension.
11.Reserpine acts by:
A. Blocking α1 receptors
B. Blocking β receptors
C. Increasing norepinephrine release
D. Depleting norepinephrine stores in nerve terminals
Rationale: Reserpine prevents vesicular storage of catecholamines.
12.Reserpine inhibits:
A. COMT
B. MAO
C. Tyrosine hydroxylase
D. VMAT (vesicular monoamine transporter)
Rationale: VMAT inhibition prevents storage of monoamines in vesicles.
, 13.Which neurotransmitter is depleted by reserpine?
A. Acetylcholine only
B. GABA only
C. Histamine only
D. Norepinephrine, dopamine, and serotonin
Rationale: Reserpine depletes multiple monoamines.
14.A major limitation of reserpine therapy is:
A. Severe hyperglycemia
B. Depression
C. Renal stones
D. Hyperthyroidism
Rationale: Monoamine depletion may produce severe depression.
15.Centrally acting α2 agonists generally produce:
A. Increased heart rate
B. Increased sympathetic tone
C. Bradycardia
D. Increased contractility
Rationale: Reduced sympathetic outflow decreases heart rate.
16.Which drug may be administered as a transdermal patch?
A. Methyldopa
B. Reserpine
C. Guanethidine
D. Clonidine
Rationale: Clonidine is available in oral and transdermal forms.
17.Clonidine is also used clinically for:
A. Hyperthyroidism
B. Glaucoma only
C. ADHD
D. Peptic ulcer disease
ANTIADRENERGIC AGENTS PRACTICE QUESTION
AND ANSWERS 2026-2027 UPDATE EXAM | 100%
VERIFIED CORRECT ANSWERS A+ GRADED.
1. Indirect-acting antiadrenergic agents primarily lower blood pressure by:
A. Blocking β1 receptors directly
B. Blocking α1 receptors directly
C. Reducing sympathetic activity without directly blocking peripheral
adrenergic receptors
D. Increasing parasympathetic activity
Rationale: These drugs reduce adrenergic stimulation indirectly through central
or neuronal mechanisms.
2. Which two major groups comprise indirect-acting antiadrenergic agents?
A. Alpha blockers and beta blockers
B. Centrally acting α2 agonists and adrenergic neuron-blocking agents
C. Cholinergics and anticholinergics
D. Calcium channel blockers and ACE inhibitors
Rationale: Indirect antiadrenergics are classified into centrally acting α2
agonists and neuron-blocking agents.
3. Which drug is a centrally acting α2-adrenergic agonist?
A. Prazosin
B. Phenoxybenzamine
C. Propranolol
D. Clonidine
Rationale: Clonidine lowers blood pressure by stimulating central α2 receptors.
4. Clonidine lowers blood pressure mainly by:
A. Increasing cardiac output
, B. Blocking α1 receptors
C. Reducing sympathetic outflow from the CNS
D. Increasing norepinephrine release
Rationale: Activation of central α2 receptors suppresses sympathetic discharge.
5. The principal receptor involved in the antihypertensive action of clonidine
is:
A. α1
B. β1
C. β2
D. α2
Rationale: Central postsynaptic α2 receptors mediate the antihypertensive
effect.
6. Which drug is considered a prodrug that is converted to α-
methylnorepinephrine?
A. Guanfacine
B. Clonidine
C. Methyldopa
D. Reserpine
Rationale: Methyldopa must be converted in the CNS to its active metabolite.
7. Methyldopa is especially important in treating:
A. Heart failure
B. Migraine
C. ADHD
D. Hypertension during pregnancy
Rationale: Methyldopa has a long history of safe use in pregnancy-associated
hypertension.
8. Which adverse effect is common with clonidine therapy?
A. Hyperactivity
B. Tachycardia
, C. Dry mouth
D. Diarrhea
Rationale: Xerostomia is one of the most common adverse effects.
9. Abrupt discontinuation of clonidine may result in:
A. Severe bradycardia
B. Heart block
C. Hypoglycemia
D. Rebound hypertension
Rationale: Sudden withdrawal can trigger excessive sympathetic activity.
10.Which centrally acting α2 agonist has a longer half-life and less rebound
hypertension than clonidine?
A. Methyldopa
B. Reserpine
C. Guanfacine
D. Prazosin
Rationale: Guanfacine’s longer duration reduces withdrawal-related
hypertension.
11.Reserpine acts by:
A. Blocking α1 receptors
B. Blocking β receptors
C. Increasing norepinephrine release
D. Depleting norepinephrine stores in nerve terminals
Rationale: Reserpine prevents vesicular storage of catecholamines.
12.Reserpine inhibits:
A. COMT
B. MAO
C. Tyrosine hydroxylase
D. VMAT (vesicular monoamine transporter)
Rationale: VMAT inhibition prevents storage of monoamines in vesicles.
, 13.Which neurotransmitter is depleted by reserpine?
A. Acetylcholine only
B. GABA only
C. Histamine only
D. Norepinephrine, dopamine, and serotonin
Rationale: Reserpine depletes multiple monoamines.
14.A major limitation of reserpine therapy is:
A. Severe hyperglycemia
B. Depression
C. Renal stones
D. Hyperthyroidism
Rationale: Monoamine depletion may produce severe depression.
15.Centrally acting α2 agonists generally produce:
A. Increased heart rate
B. Increased sympathetic tone
C. Bradycardia
D. Increased contractility
Rationale: Reduced sympathetic outflow decreases heart rate.
16.Which drug may be administered as a transdermal patch?
A. Methyldopa
B. Reserpine
C. Guanethidine
D. Clonidine
Rationale: Clonidine is available in oral and transdermal forms.
17.Clonidine is also used clinically for:
A. Hyperthyroidism
B. Glaucoma only
C. ADHD
D. Peptic ulcer disease
