For systemic mycosis fluconazole is preferred over ketoconazole because of –
Correct Answer: All the above
Description: Ans. is 'd' i.e., All the above Imidazoles and Triazoles* These are presently the most extensively used antifungal drugs.* Four imidazoles are entirely topical, while ketoconazole is used both orally and topically.* Two triazoles fluconazole and itraconazole have largely replaced ketoconazole for systemic mycosis because of greater efficacy, Longer 11/2, fewer side effects and drug interactions.* The imidazoles and triazoles have broad spectrum antifungal activity covering dermatophytes, Candida, other fungi involved in deep mycosis (except mucor), Nocardia, some gram positive and anaerobic bacteria, e.g.* Staph, aureus, Strep, faecalis, Bac. fragilis and Leishmania.* The mechanism of action of imidazoles and triazoles is the same. They inhibit the fungal cytochrome P450 enzyme Tanosterol 14-demethylase' and thus impair ergosterol synthesis leading to a cascade of membrane abnormalities in the fungus.* The lower host toxicity of triazoles compared to imidazoles has correlated with their lower affinity for mammalian CYP450 enzymes and lesser propensity to inhibit mammalian sterol synthesis.* However, because they are active against certain bacteria as well (which do not have ergosterol), other mechanisms of action also appear to be involved.
Category:
Pharmacology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now