Pre-exposure prophylaxis (PrEP) for HIV prevention

What is PrEP?#

Pre-exposure prophylaxis (PrEP) is an oral medication taken by HIV-negative people to protect them from contracting HIV. When taken correctly, it is up to 99% effective at preventing HIV.

PrEP is a single tablet that contains two antiretroviral medicines also used to treat HIV. It is usually taken every day, but it can also be taken on-demand around the time of possible exposure. Because the dosing instructions must be followed closely for protection, it is important to see a doctor for guidance on which approach is right for you. PrEP is not for everyone, and other HIV prevention options are also available.

Who PrEP is for#

PrEP is for HIV-negative people who are at risk of HIV infection. This can include people who:

• have a sexual partner with HIV who is not on treatment
• are otherwise at high risk of acquiring HIV
• are sexually active and use condoms inconsistently

Your personal circumstances and your level of risk of being exposed to HIV should all help guide the decision about whether PrEP is right for you. Speak with your doctor to see if PrEP is your best option.

How effective PrEP is#

Studies show that PrEP is highly effective at preventing HIV when taken consistently as prescribed. It can reduce the risk of getting HIV by up to 99%.

PrEP must be taken as prescribed for maximum protection.

Possible side effects#

Most people who take PrEP do not experience side effects. Some people may have mild effects that usually settle within the first month, such as nausea, loss of appetite or headaches.

A small proportion of people on PrEP may develop changes in kidney function, so kidney tests are important about every 6 months while taking it. If you have any concerns about side effects, see your doctor.

Tests and monitoring#

At your first appointment, and before starting PrEP, your doctor will check your health and arrange some tests. These usually include:

• an HIV test
• a full sexually transmissible infection (STI) test
• kidney and liver function tests

You will also receive information about how to reduce your risk of HIV infection. While on PrEP, see your doctor regularly (for example, every 3 months) for repeat HIV and STI tests and for a new prescription. It is important to have a sexual health test regularly even if you have no symptoms.

PrEP does not protect against other STIs such as syphilis, gonorrhoea and chlamydia. Condoms and lubricant can help protect against and reduce the spread of STIs.

How long to take PrEP#

The length of time people need to be on PrEP depends on their personal circumstances. People may stop taking PrEP if:

• their risk of HIV infection becomes low because of lifestyle changes
• they find it hard to take medication regularly, or often forget doses
• side effects are interfering with their life

Your doctor may also decide that other prevention options would work better for you. Talk with your doctor if you are having trouble remembering to take your medication or if you want to stop PrEP. If you do stop, it is important to keep taking PrEP for 28 days after your last possible exposure to HIV before ceasing it.

Other ways to prevent HIV#

As well as PrEP, the risk of HIV transmission can be reduced by:

• using condoms (including internal condoms) with water- or silicone-based lubricant during anal or vaginal sex
• using condoms or dental dams during oral sex
• using clean, sterile injecting equipment
• if you have HIV, taking antiretroviral treatment as prescribed to reach and maintain an undetectable viral load (U=U)
• having regular sexual health checks
• taking post-exposure prophylaxis (PEP) if you think you have been exposed to HIV

Depending on your risk factors and lifestyle, other prevention methods may suit you better. Finding the right method, or combination of methods, that works for you and your partners is important. Speak to your doctor or a sexual health clinician for more information.

Key points#

• When taken daily, or on-demand under the advice of a doctor, PrEP is up to 99% effective at preventing HIV.
• It is important to see a doctor for guidance on how to follow the dosing instructions for protection against HIV.
• PrEP isn’t for everyone, and there are other HIV prevention options available.
• PrEP is for HIV-negative people at risk of HIV infection.
• This includes having a sexual partner who has HIV and is not on treatment, or otherwise being at high risk of getting HIV.

Where to get help#