PrEP (Pre Exposure Prophylaxis), also sold under the brand name Truvada, has recently been shown through clinical trials, to be effective at reducing the risk of getting HIV in high risk groups by more than 90%, when used correctly.

If you are starting or already taking PrEP privately to protect yourself against HIV, it is important to make sure you continue to take it as instructed. Remember to take it at the same time every day. If you struggle to remember when to take your medication, you can set a reminder on your phone to notify you when your next dosage is due. You can also try placing your medicine somewhere where you will remember to take it.

While it greatly reduces your chances, PrEP does not guarantee that you won’t contract HIV or other STIs, such as gonorrhoea or syphilis. For this reason, it’s important to practice safe sex and undergo regular screening to ensure that the medicine remains effective. Read on to see how you can remain safe while taking PrEP.


  • HIV and STI tests


PrEP should only be used by people who have tested HIV negative and continue to be HIV negative while taking the drug. The reason this is important is because if you later become HIV positive and you are still taking PrEP unknowingly, there is risk of becoming resistant to other HIV treatment in the long term, as PrEP contains two of the drugs used to treat HIV infection.

Besides a short seroconversion illness, which causes flu like symptoms, there are no other symptoms to indicate that you have HIV. The only way to know for certain whether or not you have HIV is to get tested.

You should aim to get tested for HIV every 3 months while you are on PrEP. It is also useful to regularly get testing for other STIs, such as chlamydia and syphilis, in addition to HIV testing because PrEP does not protect you from getting other STIs.

You can get free HIV and STI testing on the NHS and a number of clinics can even provide same day results. If you do not want to visit the clinics for testing in person, you can use a home HIV testing kit which are available online.

Some examples of where you can get free HIV and STI testing in the UK are:

  • sexual health or genitourinary medicine (GUM) clinics
  • GP surgeries
  • contraception and young people’s clinics
  • local drug dependency services
  • an antenatal clinic, if you’re pregnant

You can also pay privately for HIV and STI testing.


  • Kidney function tests


The two drugs in PrEP (emtricitabine and tenofovir), are passed out in urine through the kidneys after they have been processed in the body.

If your kidneys develop problems while taking PrEP, the drugs may be unable to pass out and build up in your body, causing more damage to your kidneys. It is therefore recommended you check your kidney function before starting PrEP, and once a year afterwards.

However, people with pre-existing kidney problems or those with conditions that could damage their kidneys in the long term (such as diabetes or hypertension), should check their kidney function every 6 months after starting PrEP.


  • Interactions with other medications


Before starting PrEP, you should make sure you tell your GP about any other medicines you are currently taking, as they could interact with PrEP and affect its effectiveness.

Some examples of drugs that may interact with PrEP are:

  • Drugs for treating fungal infections
  • Drugs for treating viral infections
  • Antibiotics
  • Painkillers
  • Medications for treating Hepatitis C
  • Cancer drugs

If you are taking a hormonal contraceptive pill, you should speak to your doctor before taking PrEP to ensure that there are no interactions between PrEP and the oral contraceptive you take.


  • Safe sex


Just because you or your partner are taking PrEP, you shouldn’t disregard the use of condoms.

When used correctly, condoms can help reduce your risk of getting HIV and other STIs, while also preventing unwanted pregnancy. 

It is important to use condoms every time you engage in unprotected anal, oral or vaginal sex to protect you and your partner from STIs and unwanted pregnancy.

You can get condoms for free on the NHS from GP surgeries and sexual health clinics, or you can buy them yourself from pharmacies, supermarkets or online.

Intravenous drug use

Intravenous (IV) drugs users have an increased risk of contracting HIV and other blood diseases including Hepatitis C by sharing needles with other people.

If you are currently an IV drug user, there are local authorities and pharmacies that have needle sharing programmes where you can exchange your used needles for clean new needles, which in turn can help reduce your risk of getting HIV and other diseases.


  • Keeping a supply of PrEP


PrEP needs to be taken daily in order to remain effective. Therefore, you should make sure that you have a supply of PrEP. You can buy PrEP online from private online pharmacies, such as Prescription Doctor, which take the hassle out of getting the treatment.

If you have a prescription for PrEP, you will need to remember to pick up the medicine from a pharmacy. Alternatively, some pharmacies can take your prescription, dispense the medicine and deliver it to your door.

No matter how you get your PrEP, you should regularly renew your prescription to ensure you have a supply of this live changing medication.