As with all other non-nucleoside reverse transcriptase inhibitors (NNRTIs), resistant virus emerges rapidly when efavirenz is administered as monotherapy.
Nii nagu teistegi mittenukleosiid- pöördtranskriptaasi inhibiitorite (non- nucleoside reverse transcriptase inhibitor, NNRTI) korral, arenevad efavirensi monoteraapia kasutamisel viiruse resistentsed tüved kiiresti.