What is the Difference Between Fluconazole and Itraconazole?

Fluconazole and itraconazole are both antifungal medications used to treat Candida fungal infections, but they have some differences in their efficacy, spectrum of activity, and side effects. Here are the main differences between the two:

1. Spectrum of Activity: Fluconazole is effective in treating infections caused by Candida spp., while itraconazole has antifungal activity against both Candida spp. and Aspergillus spp..
2. Resistance: Long-term therapy and repeated treatment with fluconazole can lead to resistance, while itraconazole can be used as an alternative therapy for patients with resistance to fluconazole.
3. Penetration of Cerebrospinal Fluid (CSF): Fluconazole has the highest ability to penetrate the CSF, followed by itraconazole and voriconazole.
4. Elimination: Fluconazole is the only azole antifungal eliminated via the kidney, while other azole antifungals, including itraconazole, are eliminated via the liver.
5. Tolerability: Itraconazole has been associated with poor tolerability, limiting its success as prophylactic therapy. Fluconazole has an average rating of 6.4 out of 10 from a total of 527 ratings on Drugs.com, with 52% of reviewers reporting a positive effect and 29% reporting a negative effect. Itraconazole has an average rating of 7.1 out of 10 from a total of 55 ratings on Drugs.com, with 60% of reviewers reporting a positive effect and 22% reporting a negative effect.
6. Formulations: Itraconazole is available in several different forms, such as oral capsules, oral solution, and intravenous solution. Fluconazole is available in various forms, including tablets, suspension, and intravenous solution.

In summary, fluconazole and itraconazole are both effective in treating Candida infections, but itraconazole has a broader spectrum of activity, including Aspergillus spp. Fluconazole has a higher penetration of the CSF and is eliminated via the kidney, while itraconazole is eliminated via the liver and has a more diverse formulation range. Tolerability and side effects may vary between the two medications, with itraconazole being associated with poor tolerability in some cases.

Comparative Table: Fluconazole vs Itraconazole

Fluconazole and itraconazole are both antifungal medications, but they have some differences in their activity against various fungi and their side effects. Here is a table summarizing the differences between fluconazole and itraconazole:

In summary, fluconazole is more active against Candida species, some dimorphic fungi, and dermatophytes, while itraconazole has a broader range of activity, including activity against Aspergillus. Fluconazole has a higher bioavailability, meaning more of the drug is absorbed into the bloodstream, while itraconazole has a lower bioavailability. The side effects for both medications can include headache, diarrhea, and nausea, but some side effects may differ. Fluconazole is available under the trade name Diflucan, and itraconazole is available under the trade name Sporanox.