Hæmningsgraden af forskellige CYP3A4 substrater er vanskelig at forudsige, Levviax bør derfor ikke anvendes under behandling med andre midler, der er CYP3A4 substrater, med mindre at
Hence, Levviax should not be used during treatment with medicinal products that are CYP3A4 substrates, unless plasma concentrations of the CYP3A4 substrate, efficacy or adverse events can be closely monitored.