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Emtricitabine and tenofovir (PrEP)

Brand names: Truvada, Descovy

Emtricitabine-tenofovir, taken daily as PrEP, greatly lowers the chance of getting HIV. It's also part of HIV treatment.

Brand namesTruvada, Descovy
Type of medicineHIV medicine (PrEP)
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

PrEP is highly effective when taken as prescribed. Regular HIV and kidney tests are needed.

It doesn't prevent other STIs.

What it's used for

  • HIV prevention (PrEP)
  • Part of HIV treatment

How to take it

  • Take it every day, with or without food.
  • Get tested for HIV before starting and every 3 months.
  • Some people use an on-demand schedule; follow only your provider's plan.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Nausea
  • Headache
  • Tiredness
  • Diarrhea
Call your provider todayFlu-like illness with fever, sore throat, or rash (possible new HIV infection; get tested)
Call your provider todayPeeing much less or swelling (kidney problems)
Call your provider todayBone pain or fractures

Warnings

  • Boxed warning: only for people confirmed HIV-negative for PrEP; hepatitis B can flare when stopping.

Other medicines, foods, and alcohol

  • NSAIDs and other kidney-affecting medicines may add to kidney risk.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

PrEP can be used in pregnancy and while breastfeeding.

Missed doses, overdose, and storage

If you miss a dose

Take it as soon as you remember, unless it's almost time for your next dose. Then skip the missed dose. Don't take two doses at once.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.