Dear Dr Louise:
I’m a sexually active gay man who doesn’t always use condoms. I’d like to take PrEP so as to root without worry of getting HIV — what’s the process? Simon, St Kilda.
The first thing is for you to have a blood test to ascertain you are HIV-negative. For the test to be reliable, it’s important that you’re outside the window period for testing — normally six weeks without any incidents of condomless sex. An HIV test during the window period may indicate you are negative when in fact you are positive. (If you happen to be seroconverting when you commence PrEP you may become resistant to the drug.)
This initial consultation is also a time for a full screening for sexually transmitted infections (STIs) and baseline tests of kidney function, liver and blood count. Truvada — the brand name of the medication approved for PrEP use in Australia — is not yet available through the Pharmaceutical Benefit Scheme, meaning a private script is required at a cost of $750 for a month’s supply.
The next thing to be aware when considering PrEP is the potential side effects. The most common are nausea, headache and weight loss. However, these are only temporary and should ease off after a couple of weeks. It’s common, too, for people on PrEP to experience a small drop in bone density. This doesn’t appear to be problematic, though, as the condition doesn’t seem to exacerbate over time.
Also, a small percentage of long-term PrEP users have recorded some drop in kidney function. If kidney function impairs, it would be recommended that you stop taking the drug. Once off PrEP, your kidney function should return to normal.
As well as initial tests for bone health and kidney function, you’ll also be checked for immunity against hepatitis B (and commence a vaccination course if necessary). Be prepared, also, for questions about recreational drug use. If you’re a regular user of crystal meth, for example, you may need to be aware of tools to help with adherence.
Taking PrEP as prescribed — one pill daily — is crucial for maximum efficacy. Your prescriber will provide tips that can help remind you to take the pill regularly. Once you’re ready to start, it’ll be recommended that you commence PreP at least five days before any instance of condomless sex.
Be aware that PrEP will not protect you against STIs. So once on PreP, you’ll be monitored every 12 weeks for syphilis, gonorrhoea, chlamydia, hep C — and HIV. Your kidneys and bones will also be regularly monitored. If, at any time, you wish to stop taking PrEP, the recommendation is that you continue on for 28 days after the last episode of condomless sex.