HIV treatment can cause side effects in some people. However, not everyone experiences side effects. The most common side effects are Nausea and vomiting Diarrhea Difficulty sleeping Dry mouth Headache Rash Dizziness Fatigue Temporary pain at the injection site (for shots) Talk to your health care provider if your HIV treatment makes you sick. Your health care provider may prescribe additional medicines to help manage the side effects or may change your HIV treatment plan.