, 1995). It is known that statins

have antifungal effect, although it is worth mentioning that they only inhibit the fungal growth at relatively high concentrations, well above the maximum achievable serum levels in humans (Kivistöet al., 1998). In the present study, we detected additive or synergistic interactions between statins and azoles in many cases at concentrations clinically achievable in the human serum. Some earlier publications also reported in vitro interaction studies between certain statins and azoles (Chin et al., 1997; Nash et al., 2002; Chamilos et al., 2006); however, in these studies, only one or two statins combined with one or two other antimycotics were involved, and systematic screening of the efficient statin–azole combinations was not performed. Chin et al. (1997) detected synergistic click here and additive effects of FLV combined with FLU or ITR against different Candida species and Cryptococcus neoformans; however, FLV was used at a higher concentration than is clinically achievable (4–8 μg mL−1). Nash et al. (2002) investigated the in vitro activity of FLU in combination with clinically relevant concentrations of FLV and PRA (1 and 0.25 mg L−1, respectively) against C. albicans, but

did not observe any synergistic effect. On the other hand, Chamilos et al. (2006) demonstrated significant in vitro synergism between LOV and voriconazole against several Zygomycetes when both drugs learn more were applied in the range of clinically achievable concentrations. The activities observed for certain azole–statin combinations highlight the promise of these compounds as candidates for the treatment of opportunistic human and animal mycoses. However, the application of the azole–statin combinations is substantially limited because severe drug interactions

can arise when these drugs are coadministered. As these agents are metabolized by the same cytochrome P450 enzyme in the liver (CYP3A4), azoles CYTH4 have an effect on the pharmacokinetics of certain statins by reducing their metabolic clearance (Kivistöet al., 1998). The increased concentration of the coadministered statins in the serum may cause severe side effects in the patients, such as myositis and rhabdomyolysis (Herman, 1999; Mazzu et al., 2000). This limits their systemic administration, but the azole–statin combinations may be applicable as topical therapy for patients with oropharyngeal candidosis or other mucocutaneous infections. Furthermore, FLV and PRA have a lower potential than other statins for metabolic drug–drug interactions, as FLV is predominantly metabolized by the CYP2C9 isoenzyme (Fischer et al., 1999), whereas PRA is excreted by the renal mechanism and does not undergo significant metabolism via the cytochrome P450 system (Triscari et al., 1995). In our work, PRA alone proved to be ineffective against the investigated isolates; but it decreased the MICs of KET and MCZ fourfold in the cases of C. glabrata.