NNRTIS

The NNRTIs are extensively metabolised by cytochrome P450, particularly by CYP3A4. They are also inducers (nevirapine, efavirenz) or inhibitors (delavirdine) of CYP3A4. The NNRTIs therefore have the potential to interact with drugs metabolised by CYP3A4, and are also affected by CYP3A4 inhibitors and inducers. Delavirdine and efavirenz may also inhibit some other cytochrome P450 isoenzymes.