Itraconazole is a third generation azol, a fungicide which acts by inhibiting ergerosterol synthesis in the fungal cell membrane, and thereby disturbing fungal regeneration. It has proven to be less toxic, to have a broader spectrum of activity and to be more potent than its predecessor ketoconazole. Itraconazole is only available in therapheutics approved for human use. Pharmacokinetic studies has been performed in humans, dogs, cats and laboratory animals. Although itraconazole has been used tentatively with good effect against fungal infections in horses, no pharmacokinetic studies have yet been done.