From the Guidelines
Itraconazole is effective against both Candida parapsilosis and Trichophyton rubrum, and it should be considered as a treatment option for these infections. Itraconazole is a broad-spectrum triazole antifungal medication that works by inhibiting the synthesis of ergosterol, an essential component of fungal cell membranes. According to the British Association of Dermatologists' guidelines for the management of onychomycosis 2014 1, itraconazole has been shown to be effective in treating Candida onychomycosis, including infections caused by Candida parapsilosis. The guidelines suggest that itraconazole can be given at a dose of 200 mg per day or as pulse therapy (400 mg per day for 1 week each month) for a minimum of 4 weeks for fingernail and 12 weeks for toenail onychomycosis.
For Trichophyton rubrum infections, itraconazole is also a viable treatment option, although the British Association of Dermatologists' guidelines for the management of tinea capitis 2014 1 suggest that terbinafine and griseofulvin are generally the first-line treatments for dermatophyte infections. However, itraconazole is listed as a second-line therapy for Trichophyton infections, with a recommended dose of 50–100 mg per day for 4 weeks, or 5 mg kg−1 per day for 2–4 weeks.
Some key points to consider when prescribing itraconazole include:
- Itraconazole should be taken with food to enhance absorption, particularly with acidic beverages.
- Patients should be aware that itraconazole has significant drug interactions due to its metabolism through the CYP3A4 enzyme system, so a medication review is essential before starting therapy.
- Liver function monitoring is recommended during treatment, especially for courses longer than one month.
- Pulse therapy may be used for onychomycosis, and the treatment duration may vary depending on the severity of the infection and the patient's response to therapy.
From the Research
Itraconazole Coverage
- Itraconazole has been shown to be effective against Trichophyton rubrum in several studies 2, 3, 4, 5.
- The minimum inhibitory concentrations (MICs) of itraconazole against T. rubrum were found to be in the range of 0.015-0.25 microg ml(-1) 2 and 0.25-2.0 microg ml(-1) 3.
- Itraconazole was also found to be effective against T. rubrum isolates exhibiting resistance to fluconazole 3.
- In combination with culture extracts of Candida parapsilosis and Trichophyton mentagrophytes, itraconazole showed a synergistic effect against T. rubrum 4.
Candida parapsilosis Coverage
- There is limited information available on the effectiveness of itraconazole against Candida parapsilosis in the context of onychomycosis or dermatophyte infections.
- However, one study found that itraconazole had a synergistic effect with culture extracts of C. parapsilosis against T. rubrum 4.
- Another study used C. parapsilosis as a quality control strain to test the antifungal activity of ketoconazole, itraconazole, griseofulvin, and terbinafine against T. rubrum 3.
Trichophyton rubrum Coverage
- Itraconazole has been shown to be effective against T. rubrum in several studies 2, 3, 4, 5.
- The MICs of itraconazole against T. rubrum were found to be in the range of 0.015-0.25 microg ml(-1) 2 and 0.25-2.0 microg ml(-1) 3.
- Itraconazole was also found to be effective against T. rubrum isolates exhibiting resistance to fluconazole 3.