The fact that female sex is a risk factor for enhanced antiretroviral effects (including toxicities) has an important implication, particularly from a global health perspective as women now represent the fastest growing segment of the HIV/AIDS epidemic. Therefore, an understanding of the magnitude, clinical significance, and the mechanisms underlying this phenomenon deserves further study. Knowledge acquired from such studies will likely contribute to improved survival among female HIV-infected patients, through optimization of antiretroviral therapeutic regimens in manners that minimize serious adverse effects and improve adherence.