Weight gain is not listed as a side effect in the product information for Stribild, but a large study suggests that some of the newer HIV treatments, including those containing integrase strand inhibitors such as elvitegravir (found in Stribild), can be linked with significant weight gain. Over 96 weeks, elvitegravir was associated with a mean weight gain of 2.72 kg [6 lbs] (95% CI, 2.45–3 kg). Weight gain may also be due to:

• A “return to health” effect after years of fighting a viral infection. This is more pronounced in people with low CD4 counts or with a low baseline weight before treatment
• An increased appetite and not making healthy food choices
• Newer HIV treatments having better gastrointestinal tolerability (causing less side effects such as nausea or diarrhea).

Stribild is a four-dose fixed combination of elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (tdf) that is a complete regimen for the treatment of HIV-1 infection in adults and pediatric patients 12 years of age and older weighing at least 35kg with no prior HIV treatment history.