From the Guidelines
The recommended dose of itraconazole is 200 mg twice daily. This dose is commonly used for the treatment of various fungal infections, including candidiasis, as stated in the clinical practice guidelines for the management of candidiasis: 2009 update by the infectious diseases society of America 1. The dose may vary depending on the specific condition being treated, the patient's age, and other factors. For example, for mild to moderate disease, oral itraconazole, 200 mg 3 times per day for 3 days and then once or twice per day for 6–12 months, is recommended 1. It is essential to take itraconazole with food to enhance absorption, particularly with the capsule formulation, and to monitor blood levels to ensure adequate drug exposure 1.
Some key points to consider when prescribing itraconazole include:
- The oral solution is better absorbed on an empty stomach
- Treatment duration varies significantly based on the infection type
- Blood level monitoring may be necessary for serious infections
- Itraconazole works by inhibiting the synthesis of ergosterol, an essential component of fungal cell membranes
- Dose adjustments are necessary for patients with liver impairment, and drug interactions are common due to itraconazole's metabolism through the CYP3A4 enzyme system.
It is crucial to consult the latest clinical practice guidelines and to consider the specific needs of each patient when determining the appropriate dose and treatment duration for itraconazole.
From the FDA Drug Label
The recommended dosage of SPORANOX ® (itraconazole) Oral Solution for oropharyngeal candidiasis is 200 mg (20 mL) daily for 1 to 2 weeks. For patients with oropharyngeal candidiasis unresponsive/refractory to treatment with fluconazole tablets, the recommended dose is 100 mg (10 mL) b.i. d. The recommended dosage of SPORANOX ® Oral Solution for esophageal candidiasis is 100 mg (10 mL) daily for a minimum treatment of three weeks. Treatment should continue for 2 weeks following resolution of symptoms. Doses up to 200 mg (20 mL) per day may be used based on medical judgment of the patient's response to therapy.
The dose of itraconazole is:
- 200 mg (20 mL) daily for 1 to 2 weeks for oropharyngeal candidiasis
- 100 mg (10 mL) b.i.d. for oropharyngeal candidiasis unresponsive/refractory to treatment with fluconazole tablets
- 100 mg (10 mL) daily for a minimum treatment of three weeks for esophageal candidiasis
- Up to 200 mg (20 mL) per day based on medical judgment of the patient's response to therapy 2
From the Research
Itraconazole Dosing
- The dose of itraconazole varies depending on the specific fungal infection being treated 3.
- For the treatment of nonmeningeal, nonlife-threatening forms of blastomycosis and histoplasmosis, itraconazole was administered orally at doses of 200 to 400 mg/d 3.
- In the treatment of onychomycosis, itraconazole was given at 200 mg once daily for 3 months or intermittently at 200 mg twice daily for 1 week per month followed by a 3-week drug-free period for 3 months 4.
- The pharmacokinetics of itraconazole were compared in a multicentre, double-blind, randomized study, which showed that intermittent therapy resulted in higher maximum itraconazole plasma concentrations but lower total drug exposure, and hence lower itraconazole nail concentrations, than continuous therapy 4.
Specific Dosing Regimens
- For blastomycosis, itraconazole was administered orally at doses of 200 to 400 mg/d, with a success rate of 90% among 48 patients 3.
- For histoplasmosis, itraconazole was administered orally at doses of 200 to 400 mg/d, with a success rate of 81% among 37 patients 3.
- For onychomycosis, itraconazole was given at 200 mg once daily for 3 months or intermittently at 200 mg twice daily for 1 week per month followed by a 3-week drug-free period for 3 months, with no clear relationship observed between response to treatment and concentration of itraconazole or hydroxy-itraconazole in plasma or itraconazole in nails 4.