Raltegravir belongs to a class of drugs called integrase inhibitors (IIs). It has a powerful anti-HIV effect, and can be taken both by naive patients (people starting HIV treatment for the first time) and by treatment experienced patients. The most commonly reported side-effects are nausea and headache, but these are usually mild and go away soon after starting treatment. A recent study has found that people taking raltegravir were much more likely than people taking other HIV drugs to develop muscle pain and soreness (19 vs 3%), but they stress that this side-effect is mild and unlikely to mean that someone would need to change treatment.
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