Ergosterol and selected antifungal drugs. Current extensive research of fungi steroids biochemical pathways is resulting in number discoveries of efficient antifungal substances, having low toxicity, broad therapeutic window, wide spectrum of activity and excellent safety profile. The principal focus of this review concerns the key fungi steroid ergosterol and number of antifungal drugs used for prophylaxis and treatment of infections caused by e.g. Candida species. Particularly, the main classes of antifungal drugs including polyenes, imidazoles, triazoles, allylamines as well as new classes of antifungal agents e.g. caspofungin or anidulafungin has been characterized from drug resistance, biochemical action, molecular mechanism and treatment point of view.