Mixed acting agents – Ephedrine MCQs With Answer
Ephedrine is a classic mixed-acting sympathomimetic commonly covered in B.Pharm pharmacology. This introduction summarizes ephedrine’s mechanism of action (direct alpha/beta agonism plus indirect norepinephrine release), pharmacokinetics, clinical uses such as nasal decongestion, bronchodilation and management of hypotension, adverse effects like hypertension and insomnia, drug interactions (MAO inhibitors, TCAs, beta-blockers), and considerations for dosing and renal excretion. These focused keywords—ephedrine, mixed-acting sympathomimetic, pharmacology, mechanism of action, adverse effects, drug interactions, B.Pharm—help you revise efficiently. Now let’s test your knowledge with 50 MCQs on this topic.
Q1. What best describes the term “mixed-acting sympathomimetic” as applied to ephedrine?
- Direct stimulation of muscarinic receptors and indirect cholinergic release
- Combination of direct alpha/beta receptor agonism and indirect norepinephrine release
- Purely indirect stimulation via dopamine release only
- Selective beta-2 agonism without any alpha activity
Correct Answer: Combination of direct alpha/beta receptor agonism and indirect norepinephrine release
Q2. Which receptor types does ephedrine directly stimulate?
- NMDA and GABA receptors
- Alpha and beta adrenergic receptors
- Muscarinic and nicotinic receptors
- Histamine H1 and H2 receptors
Correct Answer: Alpha and beta adrenergic receptors
Q3. The indirect action of ephedrine primarily involves:
- Blocking acetylcholinesterase to increase ACh levels
- Enhancing release of stored norepinephrine from presynaptic terminals
- Inhibiting monoamine oxidase to prevent catecholamine breakdown
- Activating guanylate cyclase to increase cGMP
Correct Answer: Enhancing release of stored norepinephrine from presynaptic terminals
Q4. Compared to epinephrine, ephedrine typically has which pharmacodynamic characteristic?
- Shorter duration of action and more potent beta-2 effect
- Longer duration of action and less potent direct receptor activation
- Exclusive alpha-1 selectivity
- No central nervous system penetration
Correct Answer: Longer duration of action and less potent direct receptor activation
Q5. A common clinical use of ephedrine in anesthesia is:
- Treatment of malignant hyperthermia
- Prevention of postoperative nausea by H1 blockade
- Management of intraoperative hypotension due to sympathetic blockade
- Inducing neuromuscular blockade
Correct Answer: Management of intraoperative hypotension due to sympathetic blockade
Q6. Which of the following is a common adverse effect of ephedrine?
- Bradycardia and hypothermia
- Hypertension, tachycardia and insomnia
- Severe hypoglycemia and weight loss
- Profound diuresis and hyperkalemia
Correct Answer: Hypertension, tachycardia and insomnia
Q7. Ephedrine’s oral bioavailability is best described as:
- Poor due to extensive first-pass hepatic metabolism
- High, making oral administration effective for systemic effects
- Zero, only effective parenterally
- Variable and only absorbed via transdermal route
Correct Answer: High, making oral administration effective for systemic effects
Q8. Which pharmacokinetic factor most influences ephedrine elimination?
- Hepatic CYP3A4 metabolism as the primary route
- Renal excretion with urinary pH affecting clearance
- Extensive biliary excretion as the main pathway
- Rapid metabolism by plasma esterases
Correct Answer: Renal excretion with urinary pH affecting clearance
Q9. Tachyphylaxis to ephedrine is primarily due to:
- Depletion of presynaptic norepinephrine stores with repeated use
- Downregulation of hepatic metabolizing enzymes
- Immunologic antibody formation against the drug
- Renal accumulation causing toxicity
Correct Answer: Depletion of presynaptic norepinephrine stores with repeated use
Q10. Which drug interaction is most dangerous with ephedrine use?
- Concurrent use with MAO inhibitors leading to severe hypertension
- Concurrent use with antacids leading to hypokalemia
- Concurrent use with sulfonylureas causing hyperglycemia
- Concurrent use with proton pump inhibitors causing sedation
Correct Answer: Concurrent use with MAO inhibitors leading to severe hypertension
Q11. In which patient condition should ephedrine be used cautiously or avoided?
- Controlled asthma requiring bronchodilators
- Hypertension and ischemic heart disease
- Postural hypotension due to autonomic dysfunction
- Common cold with nasal congestion
Correct Answer: Hypertension and ischemic heart disease
Q12. Which statement about ephedrine’s effect on bronchi is correct?
- It is a potent, selective muscarinic antagonist used in COPD
- It provides bronchodilation via beta-2 adrenergic stimulation
- It causes bronchoconstriction through alpha-1 activation
- It has no effect on bronchial smooth muscle
Correct Answer: It provides bronchodilation via beta-2 adrenergic stimulation
Q13. A distinguishing structural feature of ephedrine compared to epinephrine is:
- Absence of a catechol ring and presence of a beta-hydroxylated phenethylamine scaffold
- Presence of an additional benzyl ring making it lipophilic
- Attachment of a phosphate group increasing water solubility
- Inclusion of an imidazole ring conferring H2 activity
Correct Answer: Absence of a catechol ring and presence of a beta-hydroxylated phenethylamine scaffold
Q14. Which stereochemical fact about ephedrine is true?
- Ephedrine is achiral and has no stereoisomers
- It has a single chiral center and exists as enantiomers with different activities
- It is a meso compound with identical enantiomers
- All stereoisomers of ephedrine are pharmacologically identical
Correct Answer: It has a single chiral center and exists as enantiomers with different activities
Q15. Pseudoephedrine differs clinically from ephedrine mainly by:
- Being a stronger direct alpha agonist and more CNS stimulant
- Having less central nervous system stimulation and primarily decongestant action
- Acting as a selective beta-1 blocker
- Not being orally active and only used intravenously
Correct Answer: Having less central nervous system stimulation and primarily decongestant action
Q16. Which lab parameter is most likely to change after ephedrine overdose?
- Serum potassium may decrease due to beta-2 stimulation
- Serum creatinine will acutely rise due to hepatic failure
- Serum amylase will fall dramatically
- Platelet count will increase twofold
Correct Answer: Serum potassium may decrease due to beta-2 stimulation
Q17. Ephedrine is contraindicated or used with extreme caution in patients taking which psychiatric medication?
- SSRIs due to excessive sedation risk
- Monoamine oxidase inhibitors due to hypertensive crisis risk
- Benzodiazepines due to respiratory depression
- Lithium due to immediate renal excretion blockade
Correct Answer: Monoamine oxidase inhibitors due to hypertensive crisis risk
Q18. Mechanism by which urinary pH affects ephedrine excretion is:
- Acidic urine increases ionization and enhances renal elimination
- Alkaline urine converts ephedrine to inactive metabolites in urine
- Urinary pH has no effect on ephedrine excretion
- Acidic urine promotes reabsorption of ephedrine in the renal tubule
Correct Answer: Acidic urine increases ionization and enhances renal elimination
Q19. Which of the following clinical scenarios is an appropriate therapeutic use of ephedrine?
- Chronic long-term monotherapy for hypertension
- Short-term treatment of spinal anesthesia-induced hypotension
- Treatment of acute myocardial infarction to reduce cardiac workload
- Management of bacterial sinusitis as an antibiotic adjuvant
Correct Answer: Short-term treatment of spinal anesthesia-induced hypotension
Q20. What is the primary reason ephedrine can cause insomnia and agitation?
- Peripheral histamine release leading to wakefulness
- Central stimulation after crossing the blood–brain barrier
- GABAergic inhibition in the cortex
- Direct cholinergic activation of the reticular formation
Correct Answer: Central stimulation after crossing the blood–brain barrier
Q21. Which statement about ephedrine’s metabolism is most accurate?
- It is completely metabolized by CYP2D6 into inactive glucuronides
- It undergoes partial hepatic metabolism but a significant amount is excreted unchanged in urine
- It is metabolized in the plasma by cholinesterases
- It is exclusively eliminated via bile after conjugation
Correct Answer: It undergoes partial hepatic metabolism but a significant amount is excreted unchanged in urine
Q22. Which hemodynamic effect is characteristic after an intravenous bolus of ephedrine?
- Reflex bradycardia with vasodilation
- Increased blood pressure with reflex bradycardia or tachycardia depending on dose
- Profound decrease in cardiac output due to negative inotropy
- Immediate coronary vasodilation with hypotension
Correct Answer: Increased blood pressure with reflex bradycardia or tachycardia depending on dose
Q23. Repeated oral use of ephedrine for nasal decongestion can lead to:
- Tachyphylaxis and rebound nasal congestion (rhinitis medicamentosa)
- Permanent cure of allergic rhinitis
- Renal stone formation due to crystalluria
- Chronic hypoglycemia due to pancreatic overstimulation
Correct Answer: Tachyphylaxis and rebound nasal congestion (rhinitis medicamentosa)
Q24. Ephedrine’s effect on intraocular pressure is generally:
- It markedly decreases intraocular pressure and is used in glaucoma
- It can increase intraocular pressure due to mydriasis and vasoconstriction
- It has no effect on eye physiology
- It induces miosis and lowers pressure acutely
Correct Answer: It can increase intraocular pressure due to mydriasis and vasoconstriction
Q25. Which sign would most likely indicate ephedrine overdose in a patient?
- Excessive salivation and bradycardia
- Severe hypertension, tachyarrhythmia and agitation
- Pupil constriction and depressed consciousness
- Profound muscle weakness and loss of tendon reflexes
Correct Answer: Severe hypertension, tachyarrhythmia and agitation
Q26. Which of the following best explains why ephedrine is sometimes abused for performance enhancement?
- It acts as a muscle anabolizer directly increasing protein synthesis
- It provides CNS stimulation, increased alertness and modest weight loss via sympathomimetic effects
- It causes long-term sedation and pain relief aiding recovery
- It selectively increases growth hormone without adrenergic effects
Correct Answer: It provides CNS stimulation, increased alertness and modest weight loss via sympathomimetic effects
Q27. Interaction between ephedrine and nonselective beta-blockers may cause:
- Complete antagonism with no cardiovascular change
- Enhanced beta effects leading to hypotension
- Unopposed alpha-mediated vasoconstriction and severe hypertension
- Profound bradycardia due to combined negative chronotropy
Correct Answer: Unopposed alpha-mediated vasoconstriction and severe hypertension
Q28. Which patient population should receive reduced caution but not absolute contraindication when prescribing ephedrine?
- Patients with well-controlled angina pectoris
- Pregnant patients in labor for treatment of spinal hypotension under supervision
- Children under 2 years for OTC decongestants
- Patients with untreated hyperthyroidism as first-line therapy
Correct Answer: Pregnant patients in labor for treatment of spinal hypotension under supervision
Q29. Which of the following is the correct explanation for ephedrine’s longer duration of action compared to catecholamines?
- It is rapidly degraded by COMT leading to prolonged metabolites
- It lacks a catechol hydroxyl pattern and is less susceptible to COMT and MAO degradation
- It is stored in adipose tissue and slowly released over weeks
- It is converted to an active prodrug that prolongs activity
Correct Answer: It lacks a catechol hydroxyl pattern and is less susceptible to COMT and MAO degradation
Q30. Which clinical measurement is most useful to monitor when giving ephedrine IV during surgery?
- Serum albumin concentration
- Continuous blood pressure and heart rate monitoring
- Fasting blood glucose every 5 minutes
- Daily urine output only
Correct Answer: Continuous blood pressure and heart rate monitoring
Q31. What is the primary therapeutic reason ephedrine is used in obstetric anesthesia?
- To induce labor via uterine contractions
- To prevent fetal tachycardia
- To treat maternal hypotension while maintaining uteroplacental perfusion
- To provide maternal sedation during cesarean section
Correct Answer: To treat maternal hypotension while maintaining uteroplacental perfusion
Q32. Which characteristic differentiates ephedrine from amphetamines in terms of mechanism?
- Ephedrine has purely dopaminergic effects while amphetamines are cholinergic
- Both are identical in mechanism and legal status
- Ephedrine has both direct receptor agonism and indirect NE release, while amphetamines mainly cause massive monoamine release and CNS stimulation
- Amphetamines primarily act as beta-blockers clinically
Correct Answer: Ephedrine has both direct receptor agonism and indirect NE release, while amphetamines mainly cause massive monoamine release and CNS stimulation
Q33. Which statement is correct regarding ephedrine dosing for acute hypotension in adults?
- Single small IV boluses titrated to effect are commonly used
- Only high fixed oral doses are effective for immediate hypotension
- Continuous infusion is contraindicated in all cases
- Topical ocular administration is the preferred route
Correct Answer: Single small IV boluses titrated to effect are commonly used
Q34. Ephedrine causes which change in metabolic parameters at therapeutic doses?
- Marked decrease in glycogenolysis and hypoglycemia
- Stimulation of glycogenolysis and potential increase in blood glucose
- Immediate fat accumulation and hypercholesterolemia
- Suppression of thyroid hormone production
Correct Answer: Stimulation of glycogenolysis and potential increase in blood glucose
Q35. Which adverse urinary effect can occur with ephedrine due to alpha-1 stimulation?
- Improved urinary flow in benign prostatic hyperplasia
- Urinary retention due to increased sphincter tone
- Profuse urinary incontinence from detrusor overactivity
- Formation of urinary tract stones composed of ephedrine crystals
Correct Answer: Urinary retention due to increased sphincter tone
Q36. In pharmacology exams, ephedrine is often contrasted with which pure direct-acting adrenergic agonist?
- Atropine
- Norepinephrine (noradrenaline)
- Insulin
- Propranolol
Correct Answer: Norepinephrine (noradrenaline)
Q37. Which monitoring is especially important in elderly patients given ephedrine?
- Regular audiometry tests
- Frequent blood pressure, heart rate and fall risk monitoring
- Daily complete neurological imaging
- Bone density scanning
Correct Answer: Frequent blood pressure, heart rate and fall risk monitoring
Q38. Ephedrine’s legal and regulatory status in many countries is influenced by:
- Its use as an antibiotic precursor
- Its potential use in illicit synthesis of methamphetamine and abuse potential
- Its role as an essential vitamin supplement
- Its status as an anti-cancer chemotherapy agent
Correct Answer: Its potential use in illicit synthesis of methamphetamine and abuse potential
Q39. Which of the following is an expected ECG change during ephedrine toxicity?
- Sinus bradycardia with flattened T waves
- Tachyarrhythmias, possible ventricular ectopy or supraventricular tachycardia
- Complete heart block in all cases
- Pathognomonic U-waves indicating ephedrine exposure
Correct Answer: Tachyarrhythmias, possible ventricular ectopy or supraventricular tachycardia
Q40. When counseling a patient about OTC pseudoephedrine vs ephedrine-containing products, you should explain:
- They are identical with no regulatory differences worldwide
- Pseudoephedrine is often restricted due to its use in illicit synthesis but is less CNS-stimulating than ephedrine
- Both are safe in pregnancy with no caution
- Neither provides nasal decongestant effects
Correct Answer: Pseudoephedrine is often restricted due to its use in illicit synthesis but is less CNS-stimulating than ephedrine
Q41. Which coexisting condition increases the cardiovascular risk of ephedrine therapy?
- Mild seasonal allergic rhinitis only
- Ischemic heart disease and uncontrolled hypertension
- Well-controlled hypothyroidism on levothyroxine
- History of treated peptic ulcer disease
Correct Answer: Ischemic heart disease and uncontrolled hypertension
Q42. Ephedrine’s onset after IV administration is typically:
- Very slow, requiring several hours for effect
- Rapid, within minutes
- Only after 24 hours due to prodrug conversion
- Unpredictable and not suitable for acute use
Correct Answer: Rapid, within minutes
Q43. Which adverse CNS effect is most commonly associated with ephedrine at therapeutic doses?
- Significant sedation and coma
- Insomnia, nervousness and tremor
- Seizure threshold lowering in every patient
- Hallucinations as an early sign in all doses
Correct Answer: Insomnia, nervousness and tremor
Q44. In pharmacology, ephedrine is used experimentally to test which physiological response?
- Cholinergic sweat reflex
- Capacity for presynaptic catecholamine release and adrenergic responsiveness
- Renin-angiotensin system suppression
- Insulin-mediated glucose uptake in muscle only
Correct Answer: Capacity for presynaptic catecholamine release and adrenergic responsiveness
Q45. Which treatment is appropriate for severe ephedrine-induced hypertension in a patient on MAOIs?
- Immediate oral antacids and observation
- IV vasodilator such as nitroprusside under close monitoring
- Administer epinephrine to counteract hypertension
- Give high-dose aspirin to lower pressure
Correct Answer: IV vasodilator such as nitroprusside under close monitoring
Q46. Ephedrine’s cardiovascular effects include which of the following at moderate doses?
- Decreased cardiac output and systemic vasodilation
- Increased heart rate and cardiac contractility with modest vasoconstriction
- Selective coronary artery constriction only
- Marked reduction in myocardial oxygen demand
Correct Answer: Increased heart rate and cardiac contractility with modest vasoconstriction
Q47. Which patient counseling point is important for someone using oral ephedrine occasionally for congestion?
- Use continuously for months for best effect
- Avoid concomitant MAOIs and be aware of insomnia and increased heart rate
- Increase dose if no effect after one week
- Ephedrine will permanently cure nasal allergy
Correct Answer: Avoid concomitant MAOIs and be aware of insomnia and increased heart rate
Q48. Which physical exam finding would suggest excessive alpha-adrenergic activity from ephedrine?
- Mucosal pallor and decreased peripheral pulses due to vasoconstriction
- Profuse sweating and miosis from parasympathetic overdrive
- Flaccid paralysis and areflexia
- Bilateral ankle edema only
Correct Answer: Mucosal pallor and decreased peripheral pulses due to vasoconstriction
Q49. In toxicology screening, ephedrine is most likely detected by:
- Complete blood count abnormalities
- Specific urine drug tests for sympathomimetics or chromatographic analysis
- Standard liver function tests showing AST/ALT elevations
- Serum cortisol measurement
Correct Answer: Specific urine drug tests for sympathomimetics or chromatographic analysis
Q50. For a B.Pharm student, which revision focus will best prepare for exam questions on ephedrine?
- Memorizing only brand names without mechanism or interactions
- Understanding mechanism (direct/indirect), receptor effects, clinical uses, adverse effects and major interactions
- Learning irrelevant herbal uses exclusively
- Focusing only on manufacturing processes without pharmacology
Correct Answer: Understanding mechanism (direct/indirect), receptor effects, clinical uses, adverse effects and major interactions
