Final answer:
Combivir is a combination medicine that includes lamivudine and zidovudine, which are both reverse transcriptase inhibitors used in the treatment of HIV.
Step-by-step explanation:
The combo medicine Combivir includes lamivudine (3TC) and zidovudine (AZT). These two components are reverse transcriptase inhibitors that help prevent the replication of HIV within the body by targeting the early step of converting viral RNA into DNA. To combat resistance, these drugs are often used in combination, as part of a highly active anti-retroviral therapy (HAART), which makes it difficult for the virus to mutate against multiple drugs simultaneously.