Antiretroviral (ARV) drugs are medications used to treat infections caused by retroviruses, most notably the HIV virus, which leads to AIDS. These drugs work by inhibiting the virus's ability to replicate, helping to control the infection and improve the immune system's function. ARVs are typically used in combination therapy, known as HAART (Highly Active Antiretroviral Therapy), to enhance their effectiveness and reduce the risk of drug resistance. By maintaining a low viral load, antiretroviral therapy allows individuals with HIV to lead healthier lives and reduces the risk of transmission to others.