Systemic candidosis is currently a major concern among certain groups of patients at particular risk because of recent treatment modalities. To prevent spread of Candida albicans, in particular, from the orogastrointestinal tract antimycotic treatment would appear beneficial. So far, however, suitable drugs are rare. Polyenes, and in particular oral nystatin, are the main ones considered so far. More recently, the oral azoles have provided therapeutic alternatives. In this review the current role of nystatin and, in particular nystatin tablets, which are better accepted than suspensions at higher dose levels, is described, focusing on efficacy and safety as determined in controlled trials. Recent evidence suggests that oral application of nystatin tablets can be considered both efficacious and safe in the appropriate context. The relative potency of oral nystatin and systemic azoles, particularly ketoconazole and fluconazole, awaits final determination.