Itraconazole 100mg/200mg is an antifungal medication used to treat a variety of fungal infections. It belongs to the class of drugs known as triazole antifungals and works by inhibiting the growth of fungi by interfering with the synthesis of ergosterol, an essential component of fungal cell membranes. Itraconazole is commonly prescribed to treat infections caused by Aspergillus, Candida, and other fungal species, including conditions like blastomycosis, histoplasmosis, fungal nail infections, and certain types of onychomycosis (fungal infections of the nails). The 100mg or 200mg doses are typically used depending on the severity and location of the infection. It is important to follow the prescribed dosage schedule as directed by a healthcare provider, as itraconazole can have side effects such as liver toxicity, and it may interact with other medications.