Nevirapine, brand name Viramune belongs to a class of drugs known as NNRTIs. NNRTIs are nonnucleoside reverse transcriptase inhibitors. Nevirapine is used in medicine for treating HIV infections. Nevirapine can be used alone or with other medications as determined by a physician. Nevirapine normally works by blocking the growth of HIV virus in the body of a patient.