Bosentan MCQs With Answer

Introduction: Bosentan MCQs With Answer is a focused study resource designed for B.Pharm students to master clinical pharmacology of bosentan, a dual endothelin receptor antagonist. This concise, keyword-rich introduction covers mechanism of action, indications such as pulmonary arterial hypertension, pharmacokinetics (CYP3A4/CYP2C9 metabolism), dosing, adverse effects like hepatotoxicity and anemia, important drug interactions, contraindications including pregnancy, and monitoring requirements. The questions emphasize therapeutic use, safety monitoring, and counselling points to prepare students for exams and clinical practice. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. What is the primary therapeutic indication for bosentan?

• Pulmonary arterial hypertension (PAH)

Correct Answer: Pulmonary arterial hypertension (PAH)

Q2. Bosentan’s mechanism of action is best described as:

• Selective ETA receptor agonist
• Dual ETA and ETB endothelin receptor antagonist
• Nitric oxide synthase inhibitor
• Prostacyclin receptor agonist

Correct Answer: Dual ETA and ETB endothelin receptor antagonist

Q3. Which enzymes primarily metabolize bosentan?

• CYP1A2 and CYP2D6
• CYP3A4 and CYP2C9
• CYP2E1 and CYP2C19
• UGT1A1 and MAO-A

Correct Answer: CYP3A4 and CYP2C9

Q4. Typical maintenance dosing of bosentan for adults after the initial month is:

• 62.5 mg once daily
• 125 mg twice daily
• 250 mg once daily
• 10 mg twice daily

Correct Answer: 125 mg twice daily

Q5. Bosentan is contraindicated in which of the following conditions?

• Male patients with mild hypertension
• Pregnancy
• Stable angina
• Asymptomatic hyperlipidemia

Correct Answer: Pregnancy

Q6. Which adverse effect is most strongly associated with bosentan and requires routine monitoring?

• Renal failure
• Hepatotoxicity (elevated transaminases)
• Severe hypoglycemia
• Pulmonary fibrosis

Correct Answer: Hepatotoxicity (elevated transaminases)

Q7. How often should liver function tests be monitored in patients on bosentan?

• Once every 6 months
• Monthly
• Only at baseline
• Only if symptoms occur

Correct Answer: Monthly

Q8. Which of the following is a documented hematologic adverse effect of bosentan?

• Leukocytosis
• Thrombocytosis
• Hemolytic anemia
• Decreased hemoglobin (anemia)

Correct Answer: Decreased hemoglobin (anemia)

Q9. Bosentan has clinically important drug interactions because it is:

• An inhibitor of CYP3A4 only
• A substrate and inducer of CYP3A4 and CYP2C9
• Exclusively renally cleared
• A P-glycoprotein inhibitor only

Correct Answer: A substrate and inducer of CYP3A4 and CYP2C9

Q10. Which oral contraceptive issue must be considered when prescribing bosentan to women of childbearing potential?

• Bosentan increases contraceptive efficacy
• Bosentan decreases the effectiveness of ethinylestradiol-containing oral contraceptives
• Bosentan has no effect on hormonal contraception
• Bosentan acts as a contraceptive itself

Correct Answer: Bosentan decreases the effectiveness of ethinylestradiol-containing oral contraceptives

Q11. Which coadministration is contraindicated with bosentan due to risk of serious interaction?

• Warfarin
• Cyclosporine
• Low-dose aspirin
• Metformin

Correct Answer: Cyclosporine

Q12. Bosentan’s pregnancy safety category is:

• Category A
• Category B
• Category X
• Category C

Correct Answer: Category X

Q13. What is the recommended action if a patient on bosentan develops persistent ALT or AST elevations >3 times the upper limit of normal?

• Continue therapy and recheck in 12 months
• Interrupt bosentan therapy and monitor closely
• Increase bosentan dose to overcome resistance
• No action needed unless patient is symptomatic

Correct Answer: Interrupt bosentan therapy and monitor closely

Q14. Which formulation/strengths are bosentan tablets commonly available as?

• 5 mg and 10 mg
• 62.5 mg and 125 mg
• 200 mg and 400 mg
• 20 mg and 40 mg

Correct Answer: 62.5 mg and 125 mg

Q15. Which clinical benefit is expected with bosentan therapy in PAH?

• Reduction in pulmonary vascular resistance and improvement in exercise capacity
• Immediate cure of pulmonary hypertension
• Replacement of anticoagulation therapy
• Permanent increase in systemic blood pressure

Correct Answer: Reduction in pulmonary vascular resistance and improvement in exercise capacity

Q16. Which monitoring is advised monthly in women of childbearing potential taking bosentan?

• Renal ultrasound
• Serum glucose
• Pregnancy test
• Chest X-ray

Correct Answer: Pregnancy test

Q17. Which of the following signs should prompt immediate evaluation for liver injury in a patient on bosentan?

• New onset pruritus, jaundice, or dark urine
• Mild headache once weekly
• Occasional dry mouth
• Intermittent muscle cramps

Correct Answer: New onset pruritus, jaundice, or dark urine

Q18. Bosentan’s typical oral route of administration requires what patient counseling?

• Take with large fatty meal to increase absorption
• Swallow tablets whole; follow prescribed twice-daily schedule
• Crush tablets and mix with water for best effect
• Use only intravenously in hospital

Correct Answer: Swallow tablets whole; follow prescribed twice-daily schedule

Q19. Which class of drugs may have reduced plasma levels when coadministered with bosentan due to enzyme induction?

• CYP3A4-metabolized drugs like midazolam and some statins
• Renally excreted drugs like atenolol
• Drugs cleared unchanged in bile only
• Intravenous insulin formulations

Correct Answer: CYP3A4-metabolized drugs like midazolam and some statins

Q20. In patients with moderate-to-severe hepatic impairment, bosentan use is generally:

• Recommended at double dose
• Unclear but usually safe without monitoring
• Contraindicated or not recommended
• Preferred over other PAH agents

Correct Answer: Contraindicated or not recommended

Q21. Which laboratory test should be performed at baseline and periodically during bosentan therapy because of anemia risk?

• Serum potassium
• Complete blood count (hemoglobin/hematocrit)
• Fasting lipid profile
• Thyroid function tests

Correct Answer: Complete blood count (hemoglobin/hematocrit)

Q22. The pharmacological classification of bosentan is:

• Phosphodiesterase-5 inhibitor
• Endothelin receptor antagonist
• Calcium channel blocker
• Beta-adrenergic blocker

Correct Answer: Endothelin receptor antagonist

Q23. Which patient counseling point is important due to bosentan’s teratogenicity?

• Contraception is not required while taking bosentan
• Use reliable contraception and perform monthly pregnancy tests
• Bosentan enhances fertility so contraception should be stopped
• Only natural family planning is needed

Correct Answer: Use reliable contraception and perform monthly pregnancy tests

Q24. A major reason bosentan may decrease the effectiveness of warfarin is:

• Bosentan directly binds to warfarin in plasma
• Enzyme induction increases warfarin metabolism
• Bosentan competes for vitamin K absorption
• Bosentan causes renal loss of warfarin

Correct Answer: Enzyme induction increases warfarin metabolism

Q25. Which adverse effect is commonly reported and may be managed conservatively in bosentan-treated patients?

• Peripheral edema
• Acute pancreatitis
• Severe neutropenia
• Fixed drug eruption

Correct Answer: Peripheral edema

Q26. When initiating bosentan, the usual starting dose for the first 4 weeks is:

• 125 mg twice daily from day one
• 62.5 mg twice daily for 4 weeks, then 125 mg twice daily
• 10 mg once daily
• 250 mg once daily for 4 weeks

Correct Answer: 62.5 mg twice daily for 4 weeks, then 125 mg twice daily

Q27. Which population requires particular caution and frequent monitoring if prescribed bosentan?

• Postmenopausal women with osteoporosis
• Women of childbearing potential
• Patients with well-controlled asthma
• Young healthy athletes

Correct Answer: Women of childbearing potential

Q28. In addition to PAH, bosentan has been used to reduce incidence of which complication in systemic sclerosis?

• Renal crisis
• Digital ulcers
• Pulmonary embolism
• Gastroesophageal reflux

Correct Answer: Digital ulcers

Q29. Which sign would be least likely to be directly attributed to bosentan therapy?

• Elevated ALT/AST
• Significant anemia
• Teratogenic fetal abnormalities if used in pregnancy
• Profound hypoglycemia

Correct Answer: Profound hypoglycemia

Q30. For safe prescribing, what is an essential step before starting bosentan?

• Baseline liver function tests and pregnancy test in women of childbearing potential
• Baseline brain MRI
• Immediate initiation without tests to avoid delay
• Routine genetic screening for CYP2D6 only

Correct Answer: Baseline liver function tests and pregnancy test in women of childbearing potential

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