About PrEP

What is PrEP?

PrEP stands for pre-exposure prophylaxis. It is a daily tablet that reduces your chances of getting HIV through sex by almost 100%, if you don't already have it.

What is the difference between PrEP and PEP?

PrEP and PEP (post-exposure prophylaxis) are two different medications.

You should take PrEP daily if you have a high risk of getting HIV to protect yourself from this. You can find more information on this in the ‘PrEP safety information section’ of this page. Anyone can take PEP after sex if they believe they have been exposed to HIV.

You can take PrEP for as long as you believe you’re at a high risk of getting HIV. We recommend taking regular tests to check that it's still safe for you. If you want to stop PrEP or take a break, you should speak to your doctor before doing so. PEP is normally prescribed for 30 days and must be taken right after exposure to protect you from getting HIV (ideally within 24 hours).

To start PrEP, you need a prescription. You can start a consultation with Asda Online Doctor to request and order PrEP. If approved, it can quickly be delivered to your door. PrEP is also available on the NHS through a sexual health clinic. PEP is available from sexual health clinics or from A&E if it’s outside clinic working hours.

How does PrEP work?

PrEP works by stopping the virus from making copies of itself and getting into other cells in the body.

The tablet contains two active ingredients called emtricitabine and tenofovir disoproxil. These antiretrovirals are used to treat HIV infections. PreP medication is not a treatment for HIV and is for pre-exposure prophylaxis only.

We prescribe unbranded (generic) emtricitabine and tenofovir disoproxil medication for PrEP.

Do I need to get tested to take PrEP?

Yes. Before you start taking PrEP, you need to make sure:

• you are HIV negative (you can do this by taking a test via Asda Online Doctor)
• your kidney function is normal

Also, you may need to check your hepatitis status depending on your circumstances. Check your:

• hepatitis B status if you’re not vaccinated for this or don’t know this
• hepatitis C status if you were assigned male at birth, and you have sex with other men or are at higher risk of hepatitis C

It’s also recommended that you check for sexually transmitted infections (STIs) with a full screen test before you start PrEP.

PrEP testing through Asda Online Doctor

You can order our PrEP test kits to carry these tests out at home. You can choose from our:

• basic profile test to check your HIV status and kidney function only
• advanced profile test* to check all of the above (HIV status, kidney function, and hepatitis status)

We also offer a kidney function test if you only need to check this.

When your results are ready, our doctors will send you a message through your account with these plus any follow up advice.

You can order PrEP through us if you’ve not taken these tests yet but you must complete these and have your results before you start taking PrEP medication.

If you receive your medication before then, please wait until you have your test results to begin taking this. You can take these tests through your GP or another provider, if you wish.

* You should wait 8 weeks after a hepatitis B vaccination before taking a hepatitis B test. Taking a test before 8 weeks have passed may give a false positive result.

While taking PrEP

For your safety and wellbeing, you need to continue taking the tests mentioned above at various stages once you begin taking PrEP. You can order our home test kits above for this.

Every 3 months, you need to take a HIV test. It’s recommended that you regularly test for all common STIs too.

After 12 months, you need to take a HIV test and a kidney function test. If you have a high risk of kidney disease, you should take a kidney function test every 6 months instead.

You need to check your hepatitis B and C status at this stage too, if either applies to you.

If you test positive for hepatitis, we will advise you to see your GP who will refer you to a liver specialist. If your test shows abnormal kidney function, we will ask to repeat the test to check if it normalises.

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

Then you should take another HIV test 6 weeks after starting PrEP.

How to take PrEP

In clinical trials, PrEP has been shown to work when taken:

• daily where you take one tablet every day
• on demand

How you decide to take it can depend on your needs and lifestyle.

Daily PrEP

Daily PrEP is simple and effective for all types of sex (anal, vaginal, or frontal). When you first start taking daily PrEP, regardless of whether you plan to use daily dosing or event-based dosing, you should start with a double dose 2 hours before an event.

It’s best to take PrEP around the same time every day. You can take this with or without food.

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, then continue this daily

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

On demand PrEP

Updates recently made to national PrEP guidelines outline that anybody eligible for PrEP can start it with a double dose and become protected within 2 hours. On demand or ‘event-based’ dosing can provide protection for all kinds of sex, including anal, frontal and vaginal.

Taking PrEP on demand means you only take PrEP when you need to, for example, if you have sex infrequently. Depending on your needs and circumstances, follow these steps to safely take PrEP:

If you have anal sex or give frontal (vaginal) sex	Take 2 tablets 2 hours before having sex. Wait 24 hours after your initial dose, then take 1 tablet. Keep taking 1 tablet every 24 hours until you’ve not had sex for at least 2 days.  *This is called 2:1:1 dosing.
If you are a cis woman, trans, or non-binary person receiving frontal sex (vaginal)	Take 2 tablets at least 2 hours before having sex.  Wait 24 hours after your first double dose before taking 1 tablet. Continue taking 1 tablet for 7 days every 24 hours until you’ve not had sex for at least 7 days.  *This is called 2:7 dosing.

Important information on dosing:

2:1:1 dosing should not be used for people receiving frontal (vaginal) sex or in people who inject drugs, as it does not provide enough HIV prevention.

If you have sex over several days (for example, over a weekend), take 1 tablet every 24 hours after your first dose, regardless of how many times you have sex each day. Do not forget to take a tablet 24 and 48 hours after you stop having sex if eligible for 2:1:1 dosing, or every day for 7 days after you stop having sex if using 2:7 dosing.

You should take these tablets at the same time each day.

Example:

If you have sex every day from Monday to Friday, and are eligible for 2:1:1 dosing, you would take:

• 2 tablets on Monday (at least 2 hours before having sex)
• 1 tablet daily from Tuesday to Friday (at the same time as your first dose)
• 1 tablet on Saturday
• 1 tablet on Sunday

Tuesday, Thursday, Saturday and Sunday dosing (TTSS)

If you have been taking PrEP every day for at least 7 days, you may be able to switch to a reduced dosing schedule. This means taking PrEP on Tuesdays, Thursdays, Saturdays, and Sundays (TTSS).

This can be a safe and effective option for some people, particularly if event-based dosing is not suitable for you or if you experience side effects when taking PrEP every day. We will help you decide whether this option is right for you.

If you have any questions about taking PrEP, you can message our doctors through your account.

Can you get PrEP over the counter?

PrEP is not available over the counter and can only be prescribed by a doctor. PrEP is available on the NHS from sexual health clinics. Alternatively, you can get a prescription from one of our doctors and treatment delivered to your door with our online service.

PrEP side effects

Although PrEP is generally safe to take, you may get side effects while taking this.

Some common side effects of PrEP include:

• diarrhoea or vomiting
• heartburn or indigestion
• headaches
• dizziness
• tiredness or insomnia
• abnormal dreams
• rashes
• pain or feeling weak
• changes in your liver enzymes
• changes in the levels of your blood sugar and blood fats
• lowering of your white blood cells

Some less common side effects of PrEP include:

• yellowing of the eyes or skin
• change of colour in stool or urine
• fast or abnormal heartbeat
• shortness of breath

These side effects should get better after a couple of weeks, if you experience any at all. If they continue or you cannot tolerate them, contact our doctors through your account or speak to your GP.

If you’re worried about any uncommon or severe side effects, you can seek urgent medical help (for example, go to A&E).

PrEP safety information

PrEP is only suitable if you have a higher risk of getting HIV, but are currently HIV negative.

You might be at a higher risk of getting HIV if you:

• were assigned male at birth, or are non binary, and have sex with men and do not always use condoms
• 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
• have condomless anal or vaginal sex with people at higher risk of HIV

There may be other reasons that you are at a higher risk of getting HIV. If you're not sure if you are, you can message one of our doctors through your account. Otherwise, speak to your GP or local sexual health clinic.

While PrEP is highly effective at preventing HIV, there are several reasons why it may not be suitable for you. In addition to not having a high risk of getting HIV, you should not take PrEP if you have tested positive for HIV or show symptoms of HIV infection.

For example, PrEP may also not be suitable if you:

• have kidney disease
• have liver disease
• are allergic to the active ingredients, emtricitabine or tenofovir disoproxil
• have certain health conditions
• are taking certain medications

PrEP and pregnancy

If you are pregnant and want to start PrEP you should contact your midwife, GP, or local sexual health clinic. PrEP can be used in pregnancy depending on your personal health circumstances.

Our doctors will let you know if it is safe for you to use PrEP based on your medical history when you complete our consultation.

Before we can prescribe PrEP to you, we will ask you about any medications you are currently taking or have recently stopped. Certain medications may lower the protection PrEP provides for HIV or affect your kidneys.

These include:

• some painkillers
• some antibiotics
• medications for treating hepatitis C
• drugs for treating viral or fungal infections
• cancer medication

PrEP is unlikely to interact with alcohol or recreational drugs, but you should drink in moderation while taking PrEP to ensure your liver is healthy.

Even though PrEP is very effective at preventing HIV, it will not protect you from other STIs like herpes, gonorrhoea, or chlamydia. It’s important you attend regular STI screenings every 3 months if you are using PrEP. If you are pregnant or breastfeeding and are at a high risk of getting HIV, it is always best to speak to your obstetric doctor or midwife first before taking PrEP.