Emtricitabine/tenofovir disoproxil

Emtricitabine/tenofovir disoproxil is a PrEP medication prescribed to those with a higher risk of getting HIV. It can reduce the chances of HIV infection through unprotected sex by 99% when taken daily.

You may be more at risk of getting HIV if you:

• are a man, non-binary, or trans person who has unprotected (condomless) sex with men
• are HIV-negative, but your partner is HIV positive
• have sex with people from places where HIV is common
• are of black African descent
• inject drugs
• are a sex worker
• have recently migrated

If you have sex with someone without a condom, and you are not sure about their HIV status, you might be more at risk if you are:

• a man having sex with other men
• a transgender person having sex with men
• a woman having sex with bisexual people
• having sex with someone from a country with a high rate of HIV

These are only some examples of activities that could mean you’d benefit from reducing your HIV risk through taking PrEP. If you’re not sure if PrEP is right for you, message one of our doctors through your patient account, and we’d be happy to help.

Emtricitabine/tenofovir disoproxil is the most commonly used PrEP treatment in the UK. It is an unbranded medication. You may come across the same treatment under the branded name, Truvada.

The medication is named after its 2 active ingredients, emtricitabine and tenofovir disoproxil.

Emtricitabine/tenofovir disoproxil can also be used with other medications to treat HIV. Asda Online Doctor does not prescribe medication for HIV treatment if you are HIV positive already, as in this case, it’s best you get treated by an HIV specialist.

The active ingredients in emtricitabine/tenofovir disoproxil (emtricitabine and tenofovir disoproxil) are antiretroviral medicines. They work by stopping viruses from multiplying and spreading in the body.

Yes, you will need to have some tests before taking this PrEP medication. These should be done no more than 6 weeks before you start and include:

• a HIV test*, as the antiretroviral drugs in PrEP are used to treat HIV too, and you can build a resistance to these if you’re already HIV positive
• kidney function tests as PrEP can affect your kidneys

Also, you may need:

• a hepatitis B test if you have not been vaccinated or do not know your status for this
• a hepatitis C test if you are a man who has sex with other men, or are at higher risk of getting hepatitis C

PrEP can affect your condition and any future treatment you receive if you have hepatitis B or C, so it’s important to test for these conditions before starting PrEP and during your treatment if needed.

*If you've had unprotected sex before starting PrEP, you need to take an HIV test straight away and another 6 weeks after starting PrEP, to make sure this is negative. Some tests give accurate results after different times, so check with a doctor if you are not sure.

It is recommended that you regularly test for other sexually transmitted infections such as chlamydia, gonorrhoea and syphilis, too.

While taking PrEP

Once you begin taking your PrEP medication, you should take:

• an HIV test every 3 months
• an HIV test and a kidney function test** once a year, plus a hepatitis B and C test if these apply to you

If you have had sex without a condom with someone whose HIV status you are unaware of, and it has been less than 6 weeks before:

• your last HIV test
• you started PrEP

You should take another HIV test 6 weeks after starting PrEP.

**If you have a high risk of kidney disease, you should take a kidney function test every 6 months. In some cases, every 3 months is recommended, but your doctor will let you know if this applies to you.

Get tested through Asda Online Doctor

We offer 2 home PrEP test kits which cover these tests. Choose from our:

• advanced profile kit which checks your HIV status, kidney function and hepatitis status
• basic profile kit which checks your HIV status and kidney function only.

We also offer a standalone kidney function test, if this is the only thing you need to check. For example, you’ve done a HIV test separately and you don’t need to check your hepatitis status.

Order your PrEP test kit through us and get free home delivery. When your test kit arrives, collect your sample and send this away to our laboratory for analysis. Your results will be sent to your Asda Online Doctor account with advice on what to do next. You can take these PrEP tests through another provider or your GP, if you wish.

You can order emtricitabine/tenofovir disoproxil from us before you have completed these tests. However, for your safety, you must complete these tests and have your results before you start taking emtricitabine/tenofovir disoproxil. We will remind you about this when you complete your medication order.

Emtricitabine/tenofovir disoproxil should be taken once a day, with food if possible. It’s best to take this at the same time each day ('daily dosing'), though there are other ways to take PrEP (for example, 'on demand dosing').

Daily dosing

You can start taking PrEP daily by:

• taking your first 2 tablets at least 2 hours before you have sex
• taking 1 tablet the day after, around the same time, which you can continue daily

You should begin your daily dose ideally 24 hours after your first double dose to stay protected from HIV.

Recent updates to national PrEP (emtricitabine/tenofovir disoproxil) guidelines mean that if you’re eligible for it, you can start it with a double dose and be protected within 2 hours. Taking PrEP on demand (also called event-based dosing) can help protect against HIV during all types of sex, including anal, frontal, and vaginal sex.

If you do not have sex often, or you’d rather not take a tablet every day, ‘on-demand’ can be a good option. It allows you to protect yourself from HIV only when you need to. When taken correctly and on time, on-demand dosing is just as effective as daily dosing.

It’s important not to miss any doses, as missing even 1 tablet can reduce how well it works.

Depending on what works best for you, follow these steps to take emtricitabine/tenofovir disoproxil safely:

If you’ve been taking daily PrEP for at least 7 days, you may be able to switch to a TTSS dosing schedule (Tuesdays, Thursdays, Saturdays, and Sundays). This can be a suitable option if event-based dosing is not right for you, or if you get any side effects when taking PrEP every day.

You can find out more about how to take PrEP by messaging your doctor through your Asda Online Doctor account, or through your local sexual health clinic or GP.

If you vomit less than an hour after taking a tablet, you should take another tablet. If you vomit more than an hour after taking a tablet, you do not need to take another. If you take more emtricitabine/tenofovir disoproxil than you should, speak to a doctor straight away. You can call 111, go to your nearest sexual health clinic, or A&E if it's outside of clinic hours.

It is very important that you do not miss a dose of emtricitabine/tenofovir disoproxil. If you miss a dose, you could be at a higher risk of getting HIV.

If you daily dose and it has been:

• less than 12 hours after you would normally take it, take that dose as soon as you can, then continue as normal
• over 12 hours since you would normally take it, miss that dose and wait to take your next dose at the usual time

If you miss a dose, practising safe sex methods, like wearing a condom, can help reduce your chance of getting HIV.

If you event dose and miss the before sex dose:

• still take a double dose after the event and continue daily dosing
• speak to your local sexual health clinic or A&E to check if you need PEP

If you want to stop using PrEP, speak to your doctor first so they can advise how to do this safely.

Emtricitabine/tenofovir disoproxil may not be suitable if you take some medications. You should speak to your doctor before using this treatment if you take:

• medication for viral, bacterial, or fungal infections, such as ganciclovir, vancomycin, and aminoglycosides
• interleukin-2 (cancer treatment)
• regular non-steroidal anti-inflammatory drugs, used to relieve muscle or bone pains
• medication to treat hepatitis C, such as ledipasvir/sofosbuvir

You must not take emtricitabine/tenofovir disoproxil if you take any other medicines containing the same active ingredients, or other antiviral medications containing alafenamide, adefovir dipivoxil, tenofovir, or lamivudine.

Emtricitabine/tenofovir disoproxil is usually well tolerated but, as with any medication, can have some serious side effects, including:

• excess lactic acid in the blood, which may cause stomach pain, drowsiness, or rapid breathing
• autoimmune disorders, which can cause muscle weakness, hyperactivity, or palpitations
• allergic reactions
• inflammation of the liver, kidneys, or pancreas

If you notice any severe or unexpected symptoms, go to A&E or call 999 straight away.

Common side effects of emtricitabine/tenofovir disoproxil include:

• dizziness
• headaches
• feeling weak
• diarrhoea
• nausea or vomiting (feeling or being sick)
• trouble sleeping
• stomach pain
• bloating
• wind
• rashes
• allergic reactions, such as swelling or wheezing
• a reduction in white blood cells

Uncommon side effects include:

• swelling in the lips, tongue, throat, or face
• muscle pain or weakness
• inflammation of the pancreas, which can cause pain in the stomach
• a reduction in red blood cells (anaemia)
• changes to your urine
• anaemia
• yellow and itchy eyes
• lactic acidosis, causing drowsiness and difficulty with breathing

Rare side effects include:

• fatty liver
• inflammation of the liver, which may cause pain in the stomach, itching, and yellow skin
• bone pain or increased fractures
• kidney problems

Since emtricitabine/tenofovir disoproxil can cause dizziness, do not drive or use heavy machinery if you feel dizzy. If you notice any serious side effects, or your side effects do not go away after a few days, speak to your doctor. For further information on side effects, read see the patient information leaflet.

Emtricitabine/tenofovir disoproxil can affect your kidneys. If you have severe kidney disease or are currently on dialysis, this treatment is not recommended.

Emtricitabine/tenofovir disoproxil and pregnancy

If you are pregnant or breastfeeding, speak to your doctor before using emtricitabine/tenofovir disoproxil.

If you have an intolerance to sugars, speak to your doctor as emtricitabine/tenofovir disoproxil contains lactose.