Censavudine is primarily used in the treatment of HIV infection. It functions as a nucleoside reverse transcriptase inhibitor (NRTI), which helps to block the activity of the reverse transcriptase enzyme, crucial for the replication of the HIV virus. By inhibiting this enzyme, Censavudine reduces the viral load in the body and helps to slow the progression of the disease. It is often used in combination with other antiretroviral drugs as part of a highly active antiretroviral therapy (HAART) regimen to enhance its effectiveness and reduce the risk of developing drug resistance. This makes it a valuable component in managing HIV and improving the quality of life for patients.