Non-nucleoside reverse transcriptase inhibitors (NNRTI drugs) interfere with the production of new viruses. This is achieved by inhibiting the enzyme, reverse transcriptase. This enzyme allows the virus to copy its own RNA to produce viral DNA, which is then used to produce the virus. Without this enzyme, the virus cannot reproduce. In order to increase the effectiveness, these medications are used in combination with one or more of the nucleoside reverse transcriptase inhibitors.

Examples include:

• Nevirapine (Viramune)
• Delavirdine (Rescriptor)
• Efavirenz (Sustiva)