This approach could be very beneficial in developing countries. Some mutations can keep multiplying even when you are taking an antiviral drug. When this happens, the drug will stop working. However when you take more than one antiviral drug at the same time, HIV mutates much more slowly and it takes much longer for resistance to develop. Sometimes, if you develop resistance to one drug, you will also have resistance to other antiviral drugs.
Resistance can develop quickly.
It is important to follow this schedule to reduce the risk of serious side effects. When you start any antiviral treatment you may have temporary side effects such as headaches, hypertension, or a general sense of feeling ill. These side effects usually get better or disappear over time. The most common side effect of nevirapine is a skin rash, which develops in about 25 percent of people taking the drug. If the rash is uncomfortable, you should stop taking the drug.