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didanosine, ddI EC (Videx EC)

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 400 mg capsule, once a day

  • Once daily

    Videx EC 400mg

    Videx EC 400 mg

If under 133 pounds:

one 250 mg capsule, once a day

  • Once daily

    Videx EC 250mg

    Videx EC 250 mg

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

Notes on taking this medication

  • Videx EC is no longer recommended for treatment of adults with HIV; if you are taking Videx EC, please talk with your clinician about changing to a different medication.
  • Dose may need to be adjusted because Videx EC can interact with other HIV drugs; dose should be reduced to 250 mg once a day if taken with Viread, Truvada, or Atripla
  • Take on empty stomach 2 hours after or 1 hour before meal (if taken with Viread, there are no food restrictions)
  • Persons with kidney problems may need an adjustment to their dose of Videx EC

Possible side effects

  • Numbness, tingling, or pain in the hands and feet (peripheral neuropathy)
  • Nausea; vomiting; diarrhea; abdominal pain
  • Pancreatitis
  • Changes in body-fat distribution, especially fat loss

See accompanying chart: Tips for Common Side Effects

My doctor's instructions

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