HIV treatment is very complex and should be undertaken by a specialist. Most regimes include a combination of drug from different classes.
Tenofovir is also sometimes used in the treatment of chronic hepatitis B infection.
Zidovudine is a thymidine analogue which interferes in DNA synthesis of retroviruses by inhibiting DNA replication. Zidovudine inhibits the key enzyme reverse transcriptase. Human DNA polymerase is inhibited only at a conc 100 times more than that required to inhibit viral reverse transcriptase. Mammalian α-DNA polymerase is thus relatively resistant to the effect. However, ÿ-DNA polymerase in the host cell mitochondria is fairly sensitive to the compound, and this may be the basis of some unwanted effects.
NRTIs are involved in multiple interactions. Some of these are with other anti-HIV therapies, which can be synergistic. Interactions with other anti-virals and anti-fungals are also seen.
Treatment regimes for HIV are no longer as complex as they once were, however patient education about compliance is still important.
Zidovudine is given orally and well absorbed. Most is excreted unchanged in the urine.
