FAQs and multilingual resources

Not everybody experiences side effects when using PrEP. If you do, they’re usually easy to tolerate and don't last long after first starting. The most common side effect is mild nausea, which rarely lasts longer than a few days. To reduce the chance of experiencing side effects, taking PrEP with or soon after a meal often helps.

Some people find taking a PrEP pill at night works if they feel tired during the day. It’s OK to try taking it at different times of day to see what works best for you, as long as you’re still taking one PrEP pill every 24 hours or as advised by your doctor. If you're using on-demand PrEP, be sure to stick to the carefully timed dosing schedule.

As with any medicine, it's best to contact your doctor if you're concerned.

Although it's best to use PrEP as advised, missing a dose sometimes happens.

If you're a cisgender man who has sex with other men and use daily or periodic PrEP, you don't need to take extra pills. Simply start your routine again as soon as you remember later that day or the next day. For people having anal sex, PrEP still offers extremely high levels of protection, even if you miss one dose. However, if you're missing more than one dose and taking less than four pills a week, PrEP may not be able to protect you against HIV.

For anyone having vaginal or front hole sex, using PrEP every day is especially important. This is to ensure sufficient levels of drug concentration in vaginal/cervical tissues. If you have missed a dose of PrEP and had vaginal or front-hole sex without a condom, it’s best to inform your prescribing doctor as soon as possible. Make sure you keep taking one PrEP pill every day as this helps ensure your body stays protected — even after the event.

For anyone using on-demand PrEP, it is essential to not to miss any doses or it might not be able to protect you against HIV. If you've missed any doses of on-demand PrEP or had condomless sex before waiting 2 hours after the initial dose, you may need to consider a course of PEP.

Discover more about different ways to use PrEP in the Use PrEP section.

For more guidance on what to do if you've missed a dose of PrEP, including whether you should seek PEP, see What should you do if you’ve missed a dose of PrEP?

PEP (Post-Exposure Prophylaxis) is a 28-day course of medicine that helps prevent HIV. PEP should be started soon after a possible exposure to HIV. The sooner you start PEP the better, but to stand a chance of working it's best started within 72 hours after a possible exposure to HIV.

PrEP (Pre-Exposure Prophylaxis) is an ongoing HIV prevention program that uses medicine to help prevent HIV. PrEP is taken before a possible exposure to HIV and can be used for as long as you choose to remain protected against HIV.

If you're using PrEP as advised, you don't need PEP even if you are exposed to HIV. Using PrEP before a possible exposure to HIV means you're already highly protected.

If you're not using PrEP or have missed a dose of on-demand PrEP, and may have been exposed to HIV, access PEP as soon as possible. Visit the Get PEP website for information on where you can get PEP anywhere in Australia.

When using PrEP as advised, alcohol and recreational drugs are not known to affect its high levels of protection against HIV.

It’s best to discuss your use of alcohol, recreational drugs (especially if you use injecting equipment) or any other prescription medication with your doctor to make sure they provide you with the best possible healthcare.

Using alcohol or recreational drugs may reduce your sexual inhibitions and could mean you’re less likely to use a condom. In these situations, PrEP is a highly effective HIV prevention strategy that may be easier to manage through daily routine rather than making decisions in the heat of the moment.

PrEP and condoms are fully compatible for use together. Using PrEP in conjunction with condoms helps maximise your protection against HIV and most STIs.

Condoms offer protection against HIV and most STIs when used correctly every time you have sex. If a condom isn't used, it can't offer any protection. This includes not using condoms or dams for oral sex.

PrEP provides extremely high levels of protection against HIV but it doesn't protect you against any other STIs. Using a condom helps reduce the risk of STIs spreading but it doesn't eliminate the risk. This is why going for regular sexual health tests is important, even if you don't have any symptoms.

The good news about STIs is that common ones are straightforward to treat. Using PrEP involves going for routine sexual health tests at least once every three months. Testing this often helps identify any STIs that require immediate treatment, ensuring your wellbeing and preventing their spread.