Drug Detail

Emtricitabine

Last Updated June 10, 2016

Trade Names

  • Tenofovir/emtricitabine: Truvada, Adco-Emtevir, Didivir (Cipla Medpro), Tyricten, Tencitab (Aspen), Tenemine (Mylan);
  • Tenofovir/emtricitabine/efavirenz: Atripla, Citenvir, Odimune (Cipla Medpro), Atroiza (Mylan), Eftenem

Drug Classification

Nucleoside reverse transcriptase inhibitor antiretroviral

Formulations

Indications and Pharmacology

Indication: treatment of HIV infection in combination with other antiretrovirals. Together with tenofovir, recommended for treatment of HIV/hepatitis B coinfection.

SA Formulary lists off-label uses: reduction of perinatal transmission of HIV, pre-exposure prophylaxsis, and postexposure prophylaxis, all in combination with other antiretrovirals.

Mechanism of action: a cytosine analogue that is phosphorylated intracellularly to emtricitabine 5’-triphosphate, which interferes with HIV viral RNA–dependent DNA polymerase inhibiting viral replication.

Pharmacokinetics: renal excretion 86%. Half-life: serum = 10 hours; intracellular = > 20 hours.

Dosage

Adult Dose: 200 mg once daily. Take without regard to meals.

Use in Renal or Hepatic Insufficiency: Use with caution in renal and hepatic impairment.

Dosage for patients with chronic kidney disease or end-stage renal disease:

  • Creatinine clearance ≥ 50 mL/min: no adjustment.
  • Creatinine clearance 30-49 mL/min: 200 mg orally every 48 hours.
  • Creatinine clearance 15-29 mL/min: 200 mg orally every 72 hours.
  • Creatinine clearance < 15 mL/min: 200 mg orally every 96 hours.
  • Receiving haemodialysis: 200 mg orally every 96 hours (dose emtricitabine after dialysis).
  • Receiving peritoneal dialysis: unknown, use with caution.

If using emtricitabine/tenofovir:

  • Creatinine clearance ≥ 50 mL/min: no adjustment.
  • Creatinine clearance 30-49 mL/min: 1 tablet orally every 48 hours.
  • Creatinine clearance < 30 mL/min: unknown, should not use combination tablet.

Use in Pregnancy and Breastfeeding: Category B. Excreted into breast milk.

Use in Children: Included in recommended antiretroviral regimens for children.*

Warnings

US Prescribing Information Boxed Warning: lactic acidosis/hepatomegaly with steatosis has been reported with nucleoside analogues with fatal cases reported. Use with caution in patients with risk factors for liver disease and suspend treatment if a patient develops signs and symptoms.

US Prescribing Information Boxed Warning: hepatitis B virus testing should be done prior to initiation of emtricitabine and caution used in coinfected patients.

Use with caution in patients with hepatitis B infection; rebound hepatitis may occur following therapy withdrawal.

Drug–Drug Interactions

Contraindicated: none.

Precautions: none.

Considerations for Special Populations

Included in recommended regimens in pregnancy, lactation, children.*

Adverse Effects

Minimal toxicity, hyperpigmentation/skin discoloration, headache, nausea, vomiting, rash.

*South Africa National Department of Health Consolidated Guidelines, 2015.
Information from US prescribing information.
Recommendation from South African Renal Society, 2008.