Digoxin – industrial production and use MCQs With Answer

Digoxin – industrial production and use MCQs With Answer
Digoxin, a cardiac glycoside derived from Digitalis species, is essential for B. Pharm students studying manufacturing, pharmacology, and therapeutic monitoring. This introduction covers industrial production steps (extraction, purification, quality control), formulation and stability considerations, pharmacokinetics, mechanism of action (Na+/K+‑ATPase inhibition), clinical uses in heart failure and atrial fibrillation, narrow therapeutic index, toxicity, and key drug interactions. Emphasis is on practical aspects: analytical methods (HPLC, immunoassay), GMP, impurity control and dosing adjustments in renal impairment. These focused topics will help you understand both industrial and clinical perspectives. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. What is the primary botanical source used for industrial extraction of digoxin?

• Digitalis lanata
• Digitalis purpurea
• Convallaria majalis
• Nerium oleander

Correct Answer: Digitalis lanata

Q2. What is the principal molecular mechanism of action of digoxin?

• Inhibition of Na+/K+‑ATPase
• Blocking L‑type calcium channels
• Beta‑1 adrenergic receptor antagonism
• Phosphodiesterase‑III inhibition

Correct Answer: Inhibition of Na+/K+‑ATPase

Q3. Which clinical conditions are the main therapeutic indications for digoxin?

• Chronic heart failure and atrial fibrillation
• Hypertension and angina pectoris
• Acute myocardial infarction without heart failure
• Peripheral vascular disease

Correct Answer: Chronic heart failure and atrial fibrillation

Q4. How is digoxin classified pharmacologically?

• Cardiac glycoside
• Class I antiarrhythmic
• ACE inhibitor
• Loop diuretic

Correct Answer: Cardiac glycoside

Q5. What is the traditional therapeutic serum concentration range for digoxin?

• 0.5–2.0 ng/mL
• 5–10 ng/mL
• 20–50 ng/mL
• 0.005–0.02 ng/mL

Correct Answer: 0.5–2.0 ng/mL

Q6. Which organ is primarily responsible for the elimination of digoxin?

• Kidney
• Liver
• Lungs
• Skin

Correct Answer: Kidney

Q7. Which early clinical sign is characteristic of digoxin toxicity?

• Visual disturbances (yellow‑green halos)
• Hearing loss
• Severe cough
• Jaundice

Correct Answer: Visual disturbances (yellow‑green halos)

Q8. What is the specific antidote for severe digoxin poisoning?

• Digoxin‑specific antibody fragments (Digoxin immune Fab)
• Activated charcoal only
• Calcium gluconate
• Atropine alone

Correct Answer: Digoxin‑specific antibody fragments (Digoxin immune Fab)

Q9. Which commonly used antiarrhythmic increases serum digoxin concentration and risk of toxicity?

• Amiodarone
• Rifampicin
• Phenobarbital
• St. John’s Wort

Correct Answer: Amiodarone

Q10. Which electrocardiographic change is commonly seen with therapeutic digoxin effect?

• Prolonged PR interval
• Shortened QT interval
• Widened QRS complex
• ST elevation in V1–V3

Correct Answer: Prolonged PR interval

Q11. Which industrial process step is fundamental to obtain digoxin from plant material?

• Extraction of cardiac glycosides followed by purification (e.g., chromatography)
• Steam distillation of essential oils
• Hydrodistillation to obtain volatile alkaloids
• Synthetic polymerization

Correct Answer: Extraction of cardiac glycosides followed by purification (e.g., chromatography)

Q12. Which analytical technique is most commonly used for quantitative assay of digoxin during production and quality control?

• High‑performance liquid chromatography (HPLC)
• Gas chromatography (GC)
• Flame photometry
• Polarimetry

Correct Answer: High‑performance liquid chromatography (HPLC)

Q13. Which separation technique is typically employed to remove polar and nonpolar impurities during digoxin purification?

• Column chromatography
• Simple distillation
• Sublimation
• Lyophilization alone

Correct Answer: Column chromatography

Q14. Hydrolysis of digoxin’s glycosidic bonds yields which type of molecule (the aglycone)?

• Digitoxigenin (aglycone)
• Digitonin (saponin)
• Lanatoside (intact glycoside)
• Digitiformin (peptide)

Correct Answer: Digitoxigenin (aglycone)

Q15. Which administration route provides 100% bioavailability of digoxin?

• Intravenous
• Oral tablet
• Buccal
• Topical

Correct Answer: Intravenous

Q16. What is the approximate plasma half‑life of digoxin in a patient with normal renal function?

• 24–48 hours
• 2–4 hours
• 7–12 days
• 30–60 minutes

Correct Answer: 24–48 hours

Q17. How does hypokalemia affect digoxin safety?

• Increases risk of digoxin toxicity
• Reduces digoxin absorption
• Enhances renal clearance of digoxin
• Prevents digoxin binding to cardiac receptors

Correct Answer: Increases risk of digoxin toxicity

Q18. Which pharmaceutical product type requires sterile manufacturing and aseptic processing for digoxin?

• Injectable solution
• Immediate‑release tablet
• Film‑coated tablet
• Transdermal patch

Correct Answer: Injectable solution

Q19. In industrial quality control, which attribute is critical for ensuring safety of digoxin API?

• Impurity profile and limits
• Color of the raw plant leaves
• Ambient humidity of packing room only
• Supplier’s logo design

Correct Answer: Impurity profile and limits

Q20. Which laboratory method is most commonly used in clinical settings for routine therapeutic drug monitoring of digoxin?

• Immunoassay
• Gas chromatography–mass spectrometry (GC‑MS)
• Nuclear magnetic resonance (NMR)
• Flame ionization detector (FID)

Correct Answer: Immunoassay

Q21. How should digoxin dosing be altered in significant renal impairment?

• Reduce dose or increase dosing interval
• Increase dose to overcome reduced clearance
• No change required
• Switch to inhalation route

Correct Answer: Reduce dose or increase dosing interval

Q22. Which of the following is NOT a typical adverse effect of digoxin?

• Hepatotoxicity
• Nausea and vomiting
• Visual disturbances
• Cardiac arrhythmias

Correct Answer: Hepatotoxicity

Q23. Which regulatory concept must be strictly followed during industrial manufacturing of digoxin API?

• Good Manufacturing Practice (GMP)
• Only local informal practices
• Unrecorded batch blending
• Ad hoc quality checks without documentation

Correct Answer: Good Manufacturing Practice (GMP)

Q24. Which detector is commonly paired with HPLC for routine detection of digoxin during QC?

• UV detector
• Refractive index detector
• Electron capture detector
• Thermal conductivity detector

Correct Answer: UV detector

Q25. Which plant glycoside is commonly hydrolyzed during processing to yield digoxin or related glycosides?

• Lanatoside C
• Saponin A
• Digitonin B
• Quinidine

Correct Answer: Lanatoside C

Q26. What is the recommended storage condition for digoxin tablets in the pharmacy?

• Cool, dry place away from sunlight
• High humidity and 40–50°C storage
• Open shelf in direct sunlight
• Frozen at −20°C

Correct Answer: Cool, dry place away from sunlight

Q27. During extraction of plant material, which factor generally increases yield of digoxin?

• Reducing particle size of the dried leaves
• Using larger intact leaves without grinding
• Lowering extraction temperature to near 0°C always
• Avoiding solvent contact

Correct Answer: Reducing particle size of the dried leaves

Q28. Which statement best describes digoxin’s distribution in the body?

• Large volume of distribution with high tissue binding (notably cardiac tissue)
• Confined mainly to the vascular compartment only
• Remains exclusively in the liver
• Does not cross membranes into tissues

Correct Answer: Large volume of distribution with high tissue binding (notably cardiac tissue)

Q29. In the early processing of Digitalis leaves, which solvent step is commonly used to remove nonpolar impurities?

• Defatting with a nonpolar solvent (e.g., hexane)
• Direct dissolution in water only
• Supercritical CO2 without prior defatting is always avoided
• Heating to dryness without solvent

Correct Answer: Defatting with a nonpolar solvent (e.g., hexane)

Q30. Besides serum digoxin levels, which laboratory parameter is most important to monitor to reduce the risk of toxicity?

• Serum potassium concentration
• Serum bilirubin
• Serum amylase
• Fasting blood glucose

Correct Answer: Serum potassium concentration

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com