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Nucleotide reverse transcriptase inhibitor

Tenofovir disoproxil

Brand names: Viread

Tenofovir disoproxil is a nucleotide reverse transcriptase inhibitor prodrug used within combination antiretroviral regimens for HIV and for chronic hepatitis B, and as a component of HIV pre-exposure prophylaxis.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It is converted to tenofovir and then to the active diphosphate, which inhibits viral reverse transcriptase and terminates viral DNA chain elongation.

Prescribing in practice

  • It can cause renal toxicity, including proximal tubulopathy and Fanconi syndrome, so renal function must be assessed before and during treatment.
  • Discontinuation in patients co-infected with hepatitis B may precipitate severe acute hepatic flares, requiring careful monitoring.
  • It is associated with reductions in bone mineral density and should be used with caution where osteoporosis or fracture risk is a concern.

Monitoring

Monitor renal function and serum phosphate before and periodically during treatment, with hepatic monitoring after withdrawal in hepatitis B co-infection.

Counselling the patient

  • Report new bone pain, muscle weakness or reduced urine output.
  • Do not stop treatment abruptly without specialist advice if you have hepatitis B.
  • Take it regularly with your other antiretrovirals.

Evidence & guidelines

Its antiviral efficacy is well established, and use for HIV pre-exposure prophylaxis with emtricitabine is supported by trials such as iPrEx and is recommended by NICE.

Reference: BHIVA; NICE TA481; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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