Some people who have had improvements in their health are now facing increasing viral loads again. Other people cannot tolerate the drugs and are unable to take them. When people do not take their anti-HIV medicines as prescribed, HIV can develop resistance to the drugs. When a person becomes resistant to an anti-HIV medicine, the drug no longer works well against the virus. All the currently available anti-HIV drugs can cause side effects .
Side effects are undesirable symptoms such as nausea, vomiting, diarrhea, and fatigue.
HIV positive people should report all side effects, even minor ones, to their doctors. People should not stop taking the drugs or change drug doses without a doctor's approval. Preventing or treating side effects can help people take their anti-HIV medications exactly as they are prescribed. This is called being adherent . Being adherent is also the best way to prevent HIV resistance.