Mekanismen, gennem hvilken posakonazol udøver sin fungicide effekt, er en selektiv hæmning af enzymet lanosterol 14- demetylase (CYP51), der er involveret i ergosterolbiosyntesen hos gærsvampe og filamentøse fungi.
The mechanism by which posaconazole exerts fungicidal action involves the selective inhibition of the enzyme lanosterol 14-demethylase (CYP51) involved in ergosterol biosynthesis in yeasts and filamentous fungi.