Synthetic antifungal agents – Clotrimazole, Miconazole, Ketoconazole, Itraconazole, Fluconazole MCQs With Answer

Synthetic antifungal agents such as Clotrimazole, Miconazole, Ketoconazole, Itraconazole and Fluconazole form the cornerstone of antifungal therapy in both topical and systemic infections. These azoles (imidazoles and triazoles) act primarily by inhibiting lanosterol 14α‑demethylase, disrupting ergosterol synthesis and fungal membrane integrity. Key B.Pharm concepts include mechanism of action, spectrum of activity, pharmacokinetics, CYP450 drug interactions, resistance mechanisms, adverse effects and clinical uses for candidiasis, dermatophytosis, cryptococcosis and aspergillosis. Understanding formulation differences (topical vs oral vs IV), hepatic toxicity risks and therapeutic monitoring is essential for safe dispensing and counselling. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. Which enzyme is primarily inhibited by azole antifungal agents leading to ergosterol depletion?

  • Beta‑glucan synthase
  • Lanosterol 14α‑demethylase
  • Squalene epoxidase
  • Chitin synthase

Correct Answer: Lanosterol 14α‑demethylase

Q2. Clotrimazole and miconazole are classified as which type of azoles?

  • Triazoles
  • Oxazoles
  • Imidazoles
  • Thiazoles

Correct Answer: Imidazoles

Q3. Which azole has the best cerebrospinal fluid (CSF) penetration and is commonly used for cryptococcal meningitis?

  • Itraconazole
  • Ketoconazole
  • Fluconazole
  • Clotrimazole

Correct Answer: Fluconazole

Q4. A major clinical concern with systemic ketoconazole therapy is:

  • Nephrotoxicity leading to renal failure
  • Severe hematologic anemia
  • Hepatotoxicity and endocrine disturbances
  • Severe ototoxicity

Correct Answer: Hepatotoxicity and endocrine disturbances

Q5. Which azole is known for potent inhibition of CYP3A4 and many drug interactions, and has been largely replaced for systemic use due to toxicity?

  • Fluconazole
  • Ketoconazole
  • Miconazole
  • Clotrimazole

Correct Answer: Ketoconazole

Q6. Itraconazole absorption from oral capsules is significantly affected by:

  • Renal function
  • Gastric acidity
  • Plasma albumin levels
  • Time of day

Correct Answer: Gastric acidity

Q7. Which antifungal is available as topical creams, vaginal pessaries and oral lozenges commonly used for vulvovaginal candidiasis and superficial dermatophytoses?

  • Fluconazole
  • Clotrimazole
  • Itraconazole
  • Amphotericin B

Correct Answer: Clotrimazole

Q8. The primary mechanism of acquired resistance to azoles in Candida species includes:

  • Overexpression or mutation of lanosterol 14α‑demethylase and drug efflux pump upregulation
  • Increased ergosterol synthesis via alternate pathways only
  • Enhanced azole uptake into fungal cells
  • Destruction of drug by fungal enzymes

Correct Answer: Overexpression or mutation of lanosterol 14α‑demethylase and drug efflux pump upregulation

Q9. Which statement about fluconazole pharmacokinetics is correct?

  • It is highly protein bound (>99%) and hepatically cleared only
  • It has excellent oral bioavailability and is substantially excreted unchanged in urine
  • It requires acidic medium for absorption like itraconazole
  • It is inactivated in the GI tract and only available intravenously

Correct Answer: It has excellent oral bioavailability and is substantially excreted unchanged in urine

Q10. Which azole is considered to have significant negative inotropic effects and should be avoided in patients with heart failure?

  • Ketoconazole
  • Itraconazole
  • Fluconazole
  • Miconazole

Correct Answer: Itraconazole

Q11. Miconazole topical formulations act primarily for which indications?

  • Systemic aspergillosis
  • Superficial fungal infections like tinea and vulvovaginal candidiasis
  • Cryptococcal meningitis
  • Invasive candidemia

Correct Answer: Superficial fungal infections like tinea and vulvovaginal candidiasis

Q12. Which laboratory parameter should be monitored during prolonged systemic therapy with ketoconazole or itraconazole?

  • Renal ultrasound
  • Liver function tests (ALT/AST)
  • Fasting blood glucose only
  • Serum amylase

Correct Answer: Liver function tests (ALT/AST)

Q13. Fluconazole is the drug of choice for maintenance therapy in patients with:

  • Invasive aspergillosis
  • Cryptococcal meningitis after initial induction
  • Cutaneous dermatophyte infections only
  • Mucormycosis

Correct Answer: Cryptococcal meningitis after initial induction

Q14. Which azole requires dose adjustment in renal impairment due to significant renal excretion?

  • Fluconazole
  • Itraconazole
  • Ketoconazole
  • Clotrimazole topical

Correct Answer: Fluconazole

Q15. Which component of fungal cell physiology is directly depleted by azole inhibition, causing increased membrane permeability?

  • Sphingolipids
  • Ergosterol
  • Cellulose
  • Peptidoglycan

Correct Answer: Ergosterol

Q16. A patient on itraconazole reports shortness of breath and edema. The pharmacist should be concerned because itraconazole can:

  • Cause dose‑related nephritis
  • Exacerbate heart failure due to negative inotropic effects
  • Induce adrenal insufficiency acutely
  • Cause bronchodilation

Correct Answer: Exacerbate heart failure due to negative inotropic effects

Q17. Which azole is most likely to interact with warfarin via CYP inhibition leading to increased INR?

  • Topical clotrimazole with no systemic absorption
  • Ketoconazole and fluconazole via CYP inhibition
  • Itraconazole with exclusive renal elimination
  • Miconazole which is free of CYP interactions

Correct Answer: Ketoconazole and fluconazole via CYP inhibition

Q18. For oropharyngeal candidiasis in an immunocompetent patient, a topical agent choice is:

  • Oral amphotericin B IV only
  • Miconazole oral gel or clotrimazole troches
  • High‑dose oral itraconazole as first line
  • Oral fluconazole always preferred over topical

Correct Answer: Miconazole oral gel or clotrimazole troches

Q19. Which azole is associated with inhibition of adrenal and gonadal steroid synthesis and may cause gynecomastia with prolonged use?

  • Fluconazole at standard doses
  • Ketoconazole
  • Clotrimazole topical
  • Miconazole topical

Correct Answer: Ketoconazole

Q20. The oral solution formulation of itraconazole differs from capsules in that:

  • Solution requires acidic pH like capsules
  • Solution has improved absorption and does not require gastric acidity
  • Capsules are absorbed better with antacids
  • Both formulations have identical bioavailability regardless of food

Correct Answer: Solution has improved absorption and does not require gastric acidity

Q21. Which azole is commonly used as a single oral dose therapy for uncomplicated vulvovaginal candidiasis?

  • Topical miconazole only
  • Fluconazole single oral dose
  • Multiple weeks of itraconazole only
  • Ketoconazole oral single dose

Correct Answer: Fluconazole single oral dose

Q22. A common molecular mechanism by which Aspergillus develops resistance to triazoles involves:

  • Loss of cell wall chitin
  • Mutations in the cyp51A gene (lanosterol 14α‑demethylase)
  • Increased uptake of triazoles into the fungal cell
  • Production of beta‑lactamases

Correct Answer: Mutations in the cyp51A gene (lanosterol 14α‑demethylase)

Q23. Which systemic azole is highly protein bound and undergoes extensive hepatic metabolism with multiple drug interactions via CYP3A4 inhibition?

  • Fluconazole (low protein binding)
  • Itraconazole
  • Clotrimazole topical
  • Amphotericin B (not an azole)

Correct Answer: Itraconazole

Q24. When counselling a patient on topical clotrimazole cream, the pharmacist should advise:

  • Systemic absorption is extensive so monitor LFTs
  • Apply to affected area for recommended duration and avoid occlusive dressings unless specified
  • Take with food for better absorption
  • Do not use topically; it must be given orally

Correct Answer: Apply to affected area for recommended duration and avoid occlusive dressings unless specified

Q25. Fluconazole therapy may increase serum levels of which oral hypoglycemic due to CYP interactions?

  • Metformin (no CYP metabolism)
  • Glibenclamide (glyburide)
  • Insulin (not CYP metabolized)
  • Sitagliptin (renal excretion, minimal CYP effect)

Correct Answer: Glibenclamide (glyburide)

Q26. Which azole is least appropriate for treating invasive candidemia requiring central nervous system penetration?

  • Fluconazole (good CSF penetration)
  • Itraconazole (poor CSF penetration)
  • Amphotericin B plus flucytosine (alternative therapy)
  • High‑dose fluconazole (appropriate in many cases)

Correct Answer: Itraconazole (poor CSF penetration)

Q27. The topical azole that can inhibit local fungal CYP enzymes and occasionally cause systemic interactions when applied extensively is:

  • Miconazole
  • Fluconazole oral
  • Itraconazole capsule
  • Amphotericin topical

Correct Answer: Miconazole

Q28. In patients receiving long‑term fluconazole prophylaxis, which laboratory monitoring is most relevant?

  • Serum potassium only
  • Liver function tests and monitoring for signs of hepatotoxicity
  • Pulmonary function tests monthly
  • Urine culture weekly

Correct Answer: Liver function tests and monitoring for signs of hepatotoxicity

Q29. Which statement about topical versus systemic azole therapy is correct?

  • Topical azoles are preferred for localized cutaneous and mucosal infections to reduce systemic toxicity
  • Systemic azoles are always preferred for superficial tinea pedis
  • Topical azoles are ineffective against Candida species
  • Systemic therapy carries no risk of drug interactions

Correct Answer: Topical azoles are preferred for localized cutaneous and mucosal infections to reduce systemic toxicity

Q30. A pharmacist should avoid dispensing itraconazole with which of the following drugs due to risk of increased plasma levels and toxicity?

  • Proton pump inhibitors (reduce itraconazole absorption, not toxicity)
  • Simvastatin (both metabolized by CYP3A4 leading to increased statin levels and risk of myopathy)
  • Insulin (no CYP interaction)
  • Oral contraceptives (no clinically relevant interactions always)

Correct Answer: Simvastatin (both metabolized by CYP3A4 leading to increased statin levels and risk of myopathy)

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