PrEP (Emtricitabine/Tenofovir disoproxil) 200mg/245mg

What is PrEP (emtricitabine / tenofovir disoproxil)?

PrEP stands for pre-exposure prophylaxis. It is a tablet taken by people who are HIV-negative to greatly reduce their risk of getting HIV. This medicine is the generic equivalent of Truvada® and combines two antiretroviral medicines — emtricitabine 200mg and tenofovir disoproxil 245mg — in a single tablet.

• Both ingredients block an enzyme (reverse transcriptase) that HIV needs to copy itself, stopping the virus establishing an infection.
• When taken correctly, PrEP is highly effective at preventing HIV from sex.
• PrEP protects against HIV only — it does not protect against other sexually transmitted infections or pregnancy. Condoms and regular STI screening are still recommended.

How to take it

Your prescriber will confirm which option is right for you.

• Daily dosing — one tablet every day, taken with food. Protection builds up after about 7 days of daily dosing for anal sex, and about 21 days for vaginal sex. Suitable for everyone eligible.
• Event-based (2-1-1) dosing — 2 tablets 2–24 hours before sex, 1 tablet 24 hours after the first dose, and 1 tablet 24 hours after that. This option is for men who have sex with men only, is for anal-sex exposure only, and must not exceed one double-dose per 7 days.

If you miss doses or have a high-risk exposure and think you may not be protected, post-exposure prophylaxis (PEP) must be started within 72 hours — go to a sexual health clinic or A&E. Do not stop PrEP suddenly if you have hepatitis B, as this can cause a liver flare.

Pricing

*One 30-tablet pack covers a month of daily PrEP, or several event-based episodes.

Potential side effects

Common (may affect up to 1 in 10 people):

• Headache, dizziness
• Diarrhoea, nausea, vomiting, stomach pain
• Rash
• Feeling weak or tired

These are often mild and tend to settle within the first few weeks (“start-up” symptoms).

Less common but serious — seek medical advice:

• Kidney problems (tenofovir is cleared by the kidneys; your prescriber will check kidney function before and during treatment)
• Reduced bone mineral density with long-term use
• Lactic acidosis (very rare) — symptoms include rapid breathing, drowsiness and muscle pain; seek urgent help
• Hepatitis B flare if PrEP is stopped suddenly in someone with hepatitis B

Always read the patient information leaflet that comes with your medicine, and report side effects to your prescriber or via the MHRA Yellow Card scheme.

Interactions & precautions

• Didanosine (ddI) — must not be taken with emtricitabine/tenofovir (risk of pancreatitis and lactic acidosis).
• Other HIV antiretrovirals — PrEP is not appropriate alongside existing HIV treatment.
• Adefovir / cidofovir and other tenofovir-class medicines — should not be combined.
• Medicines that can affect the kidneys — aminoglycoside antibiotics, amphotericin B, foscarnet, ganciclovir/valganciclovir, aciclovir/valaciclovir, and regular high-dose NSAIDs (ibuprofen, naproxen, diclofenac) need prescriber review and possible monitoring.
• Tell your prescriber about all medicines you take, including over-the-counter products.

PrEP is not suitable if you have reduced kidney function (eGFR below 60), and needs careful management if you have hepatitis B. It is only for people who are HIV-negative.

Ingredients list (common)

Active ingredients: emtricitabine 200mg, tenofovir disoproxil 245mg.

Common excipients (may vary by manufacturer — generic, brand may vary): lactose monohydrate, microcrystalline cellulose, croscarmellose sodium, pregelatinised starch, magnesium stearate, and a film coating. Always check the patient information leaflet supplied with your specific pack for the full ingredient list, especially if you have allergies or intolerances (for example to lactose).

Information leaflet

Read the official Summary of Product Characteristics and Patient Information Leaflet on the electronic medicines compendium (EMC):

View emtricitabine / tenofovir disoproxil on medicines.org.uk/emc