University of California, San Francisco Logo

University of California, San Francisco | About UCSF | Search UCSF | UCSF Medical Center

Home > Treatment > Drug Dosing Toolkit > AZT

Retrovir, zidovudine, ZDV (AZT)

Type of Drug: Nucleoside Reverse Transcriptase Inhibitor

Nucleoside reverse transcriptase inhibitors were the first type of drug available to treat HIV. They are also known as NRTIs, nucleoside analogues, or "nukes."

When the HIV virus enters a healthy cell, it attempts to make copies of itself. It does this by using an enzyme called reverse transcriptase. NRTIs block that enzyme, so HIV cannot make new copies of itself.

Approved adult dosing

one 300 mg tablet, two times a day

  • Morning

    Retrovir 300

    AZT 300 mg

  • Evening

    Retrovir 300

    AZT 300 mg

Note: Generic formulations are available; these generic pills may have different shapes and colors than the one shown above.

Notes on taking this medication

  • No food restrictions, can take with or without food
  • Persons with kidney problems may need an adjustment of their dose of AZT
  • Cannot take AZT with Zerit

Possible side effects

  • Nausea; stomach discomfort; headache
  • Symptoms of anemia (low red blood cell count): fatigue; shortness of breath
  • More rarely: muscle wasting; neutropenia (low white blood cell count)
  • Changes in body-fat distribution

See accompanying chart: Tips for Common Side Effects

This drug is also found in the following combination pills

  • AZT + lamivudine (Combivir)
  • AZT + abacavir + lamivudine (Trizivir)

My doctor's instructions

Scroll over drug name to see other names for the drug.