Antiretroviral drugs.

The first antiretroviral drug to be licensed, zidovudine, became available in 1987. Until December 1995, the antiretroviral drugs available and approved for clinical use in the United States consisted of only 5 individual drugs belonging to a single class of antiretroviral agents, nucleoside analog reverse transcriptase inhibitors. Since then, numerous other antiretroviral drugs and classes of antiretroviral drugs have been introduced. Additional drugs and newer classes of antiretrovirals are in various stages of development. Currently, there are 22 Food and Drug Administration (FDA)-approved antiretroviral agents categorized in 4 classes of drugs: nucleoside/nucleotide analog reverse transcriptase inhibitors, nonnucleoside analog reverse transcriptase inhibitors, protease inhibitors, and fusion inhibitors. The authors review the general characteristics of each class of antiretroviral drugs, including mechanism of action, pharmacologic properties, adverse effects, and drug interactions. A synopsis of current antiretroviral treatment guidelines is also provided.