The majority of these cases have been seen when patients are taking medications called protease inhibitors. These are anti-retroviral medications designed to treat patients with HIV. It is unclear if lipodystrophy is a result of having HIV or the medication used to treat HIV. It has been suggested, but not proven, that lipodystrophy is a direct side effect of protease inhibitors. In addition, it is unknown if HIV-infected children develop significant lipodystrophy after taking protease inhibitors.