Når efavirenz gives sammen med en kalciumkanalblokker, som er et substrat for CYP3A4- enzymet, kan kalciumkanalblokkerens plasmakoncentration potentielt blive reduceret.
When efavirenz is co-administered with a calcium channel blocker that is a substrate of the CYP3A4 enzyme, there is a potential for reduction in the plasma concentrations of the calcium channel blocker.