Sparfloxacin and moxifloxacin are fluoroquinolone antibiotics important for B. Pharm students to understand in depth. This MCQ set covers mechanism of action, spectrum of activity, pharmacokinetics, clinical indications, adverse effects (QT prolongation, tendon toxicity, phototoxicity), drug interactions (multivalent cations, QT‑prolonging agents), resistance mechanisms (gyrA/parC mutations, qnr), dosage forms and regulatory status. Sparfloxacin—once valued for Gram‑positive activity but limited by phototoxicity—and moxifloxacin—an advanced respiratory quinolone with hepatic elimination and anaerobic coverage—illustrate pharmacotherapeutic trade‑offs and monitoring needs. Questions include case‑based scenarios, pharmacovigilance points and comparative drug selection. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. Which best describes the primary mechanism of action of sparfloxacin and moxifloxacin?
- Inhibition of folate synthesis
- Disruption of bacterial cell membrane
- Inhibition of bacterial DNA gyrase and topoisomerase IV
- Inhibition of 30S ribosomal subunit
Correct Answer: Inhibition of bacterial DNA gyrase and topoisomerase IV
Q2. Compared to sparfloxacin, moxifloxacin has superior activity against which group of organisms?
- Obligate anaerobes such as Bacteroides species
- Typical urinary pathogens like Proteus mirabilis
- Only Gram-negative enteric bacilli
- Fungal pathogens
Correct Answer: Obligate anaerobes such as Bacteroides species
Q3. A distinguishing adverse effect historically associated with sparfloxacin is:
- Severe renal failure
- Marked phototoxicity
- Ototoxicity leading to deafness
- Persistent hypoglycemia
Correct Answer: Marked phototoxicity
Q4. Which fluoroquinolone is commonly classified as a “respiratory quinolone” and frequently used for community‑acquired pneumonia?
- Sparfloxacin
- Norfloxacin
- Moxifloxacin
- Ciprofloxacin
Correct Answer: Moxifloxacin
Q5. The predominant route of elimination for moxifloxacin is:
- Primarily renal excretion as unchanged drug
- Primarily hepatic metabolism with minimal renal excretion
- Exclusively biliary secretion of unchanged drug
- Elimination through pulmonary exhalation
Correct Answer: Primarily hepatic metabolism with minimal renal excretion
Q6. Which statement about moxifloxacin pharmacokinetics makes it less suitable for uncomplicated urinary tract infections?
- It is extensively excreted unchanged in urine achieving very high urinary levels
- It has poor oral bioavailability
- It has low urinary excretion resulting in inadequate urinary concentrations
- It is inactivated by urine pH making it ineffective
Correct Answer: It has low urinary excretion resulting in inadequate urinary concentrations
Q7. Co‑administration of antacids or oral iron supplements with sparfloxacin or moxifloxacin leads to:
- Increased bioavailability due to enhanced absorption
- No clinically significant interaction
- Reduced absorption because of chelation with multivalent cations
- Conversion to an active metabolite increasing toxicity
Correct Answer: Reduced absorption because of chelation with multivalent cations
Q8. Which cardiac adverse effect is a shared safety concern for both sparfloxacin and moxifloxacin?
- Bradycardia leading to syncope
- QT interval prolongation with risk of torsades de pointes
- Myocardial ischemia due to coronary vasospasm
- Atrial fibrillation induction
Correct Answer: QT interval prolongation with risk of torsades de pointes
Q9. Fluoroquinolones, including sparfloxacin and moxifloxacin, are generally contraindicated in pregnancy and children because of the risk of:
- Cartilage damage and arthropathy (tendinopathy risk)
- Neural tube defects
- Severe hemolytic anemia
- Increased incidence of childhood leukemia
Correct Answer: Cartilage damage and arthropathy (tendinopathy risk)
Q10. Which genetic mutations are most commonly implicated in bacterial resistance to fluoroquinolones?
- Mutations in 16S rRNA genes
- Mutations in gyrA and parC genes encoding DNA gyrase and topoisomerase IV
- Mutations in beta‑lactamase genes
- Mutations in peptidoglycan synthesis enzymes
Correct Answer: Mutations in gyrA and parC genes encoding DNA gyrase and topoisomerase IV
Q11. What regulatory action affected sparfloxacin in many markets due to safety concerns?
- It became an over‑the‑counter medication
- It was withdrawn or use severely restricted because of phototoxicity and cardiac risks
- It was approved for pediatric use
- It was reclassified as an antiviral agent
Correct Answer: It was withdrawn or use severely restricted because of phototoxicity and cardiac risks
Q12. In Gram‑positive organisms, which bacterial enzyme is often the primary target of fluoroquinolones?
- DNA gyrase (gyrA) only
- Topoisomerase IV (parC/parE)
- Beta‑lactam binding protein
- RNA polymerase
Correct Answer: Topoisomerase IV (parC/parE)
Q13. Before initiating moxifloxacin in a patient with cardiac risk factors, which baseline test is most appropriate?
- Serum creatine kinase
- Baseline ECG to assess QT interval
- Chest X‑ray
- Serum amylase
Correct Answer: Baseline ECG to assess QT interval
Q14. A notable musculoskeletal adverse effect associated with fluoroquinolones that pharmacists must counsel patients about is:
- Osteoporosis with long‑term use
- Tendinopathy and risk of tendon rupture
- Permanent myopathy with immediate onset
- Joint hypermobility syndrome
Correct Answer: Tendinopathy and risk of tendon rupture
Q15. What is the usual dosing frequency for moxifloxacin in most systemic infections?
- Four times daily
- Three times daily
- Twice daily
- Once daily
Correct Answer: Once daily
Q16. Moxifloxacin demonstrates clinical activity against which of the following respiratory pathogens including atypicals?
- Streptococcus pneumoniae and Mycoplasma pneumoniae
- Only Staphylococcus aureus
- Only Candida species
- Only enteric Gram‑negative rods
Correct Answer: Streptococcus pneumoniae and Mycoplasma pneumoniae
Q17. Plasmid‑mediated qnr proteins contribute to fluoroquinolone resistance by:
- Enzymatically degrading the drug
- Protecting DNA gyrase/topoisomerase IV from drug binding
- Pumping drug into the periplasmic space
- Altering the bacterial cell wall permeability
Correct Answer: Protecting DNA gyrase/topoisomerase IV from drug binding
Q18. Which monitoring or counseling point is particularly important for sparfloxacin compared with some other quinolones?
- Avoidance of prolonged sun exposure due to photosensitivity risk
- Strict fluid restriction during therapy
- Use of concurrent systemic corticosteroids to reduce ADRs
- No need to avoid antacids
Correct Answer: Avoidance of prolonged sun exposure due to photosensitivity risk
Q19. Which concomitant medication would most increase the risk of QT prolongation when given with moxifloxacin?
- Oral vitamin C
- Class III antiarrhythmic such as amiodarone
- Topical nasal decongestant
- Oral metformin
Correct Answer: Class III antiarrhythmic such as amiodarone
Q20. Which formulation(s) of moxifloxacin are available for clinical use?
- Oral tablets only
- Intravenous and oral formulations, and topical ophthalmic preparations
- Topical skin cream only
- Inhaled aerosol formulation only
Correct Answer: Intravenous and oral formulations, and topical ophthalmic preparations
Q21. Structural modification of adding a methoxy group at C‑8 in fluoroquinolones (as in moxifloxacin) primarily results in:
- Decreased activity against Gram‑positive bacteria
- Improved anaerobic coverage and reduced selection of resistant mutants
- Increased likelihood of phototoxicity
- Complete renal excretion of the drug
Correct Answer: Improved anaerobic coverage and reduced selection of resistant mutants
Q22. Which adverse central nervous system effect may occur with fluoroquinolones and should be counselled to patients?
- Visual hallucinations and seizures in susceptible patients
- Progressive peripheral neuropathy only after years
- Immediate loss of taste and smell
- Irreversible cognitive decline within 24 hours
Correct Answer: Visual hallucinations and seizures in susceptible patients
Q23. A pharmacist is asked why moxifloxacin is preferred for some respiratory infections over ciprofloxacin. Which rationale is most appropriate?
- Moxifloxacin has better activity against typical and atypical respiratory pathogens including Streptococcus pneumoniae
- Ciprofloxacin has superior Gram‑positive coverage compared to moxifloxacin
- Moxifloxacin has no risk of QT prolongation
- Ciprofloxacin is only available parenterally
Correct Answer: Moxifloxacin has better activity against typical and atypical respiratory pathogens including Streptococcus pneumoniae
Q24. Which patient factor markedly increases the risk of fluoroquinolone‑associated tendon rupture?
- Concurrent corticosteroid therapy
- History of migraine headaches
- Hypothyroidism treated with levothyroxine
- Use of topical emollients
Correct Answer: Concurrent corticosteroid therapy
Q25. For severe community‑acquired pneumonia requiring IV therapy, which statement about moxifloxacin is correct?
- Moxifloxacin is ineffective when given intravenously
- Moxifloxacin IV provides reliable systemic exposure and is an option for severe CAP
- Moxifloxacin must always be combined with aminoglycosides for pneumonia
- Moxifloxacin is contraindicated in all hospitalized patients
Correct Answer: Moxifloxacin IV provides reliable systemic exposure and is an option for severe CAP
Q26. Which of the following is a common patient counselling point for both sparfloxacin and moxifloxacin?
- Take with dairy to enhance absorption
- Avoid driving or using machinery if you experience dizziness or visual disturbances
- Double the dose if a dose is missed
- They are safe in pregnancy
Correct Answer: Avoid driving or using machinery if you experience dizziness or visual disturbances
Q27. Which laboratory or clinical monitoring is most relevant during prolonged therapy with moxifloxacin?
- Frequent urine cultures in all patients
- Periodic ECGs for QT interval assessment in at‑risk patients
- Daily liver biopsies
- Routine measurement of cerebrospinal fluid drug levels
Correct Answer: Periodic ECGs for QT interval assessment in at‑risk patients
Q28. Which of the following interactions is most likely to reduce systemic exposure to moxifloxacin?
- Concurrent use of multivalent cation supplements taken with the antibiotic
- Concomitant use of acetaminophen
- Co‑administration with vitamin B12
- Taking the antibiotic with a high‑fat meal increases exposure
Correct Answer: Concurrent use of multivalent cation supplements taken with the antibiotic
Q29. A patient on moxifloxacin develops acute tendon pain and swelling; the correct immediate action is to:
- Continue therapy and add NSAIDs for pain
- Stop the fluoroquinolone immediately and avoid strenuous use of the affected tendon
- Increase the dose of moxifloxacin
- Switch to a different fluoroquinolone without stopping the current drug
Correct Answer: Stop the fluoroquinolone immediately and avoid strenuous use of the affected tendon
Q30. Which statement is TRUE regarding clinical selection between sparfloxacin and moxifloxacin?
- Sparfloxacin is preferred for urinary tract infections due to high urinary excretion
- Moxifloxacin is often chosen for respiratory infections because of its activity against Streptococcus pneumoniae and atypicals
- Both drugs are equally safe in pregnancy
- Sparfloxacin has no photosensitivity risk compared to moxifloxacin
Correct Answer: Moxifloxacin is often chosen for respiratory infections because of its activity against Streptococcus pneumoniae and atypicals
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