Ketoconazole raises
cinacalcet levels 2-fold and increased the
incidence of
cinacalcet adverse effects, probably by inhibiting the
metabolism of
cinacalcet by CYP3A4. Other
potent CYP3A4 inhibitors, such as the
protease inhibitors, are predicted to interact
similarly.
It may be prudent to monitor parathyroid hormone and
serum calcium more frequently in any patient receiving a
protease inhibitor.