Question
Can I do on-demand PrEP as 1-1-1 dosing?
16 July 2023. Related: Adherence, All topics, PrEP.
Weekly on-demand PrEP dosing?
I tend to have sex on Fridays nights. Is a double dose required when restarting on-demand PrEP on Friday mornings when the last previous dose was on Sunday?
Different pages on your website say different things about gaps of less than 7 days. Obviously a 2-1-1 pattern is needed for gaps of longer than a week, but it is unclear whether 1-1-1 is possible if taken weekly.
Answer
Hi, how are you doing?
In most cases it is fine to do this once e.g., complete the first regimen of on-demand dosing using a double dose, then restarting with a single dose within 7 days.
However this is usually on suggested as a one-off thing and not to be repeated.
Doing this regularly on a 1-1-1 dose means you are only using PrEP 3/7 days on a single dose. Not suing that initial double dose can reduce the required initial level of PrEP in your body – this is accounted for by repeating the regimen once.
For this reason it would either be recommended to always use a double dose on the Friday if you want to continue on-demand, or move to a daily regimen and build PrEP into your daily routine.
Josh.
Hi John, you would still get protection but continuing for a week is a good idea and can’t do any harm. It also sounds like the sex was no a high risk.
Hi,
I have taken 1 instead of 2 pills for on demand PREP, after that I took 1 pill per day since, its been 3 days.
I am sort of freaking out for this mistake. Should I keep taking a pill until I reach 7 days?
Would 1 pill before sex still work? I took the pill around noon and had sex at 8.30 PM and I was the bottom. He didnt cum inside me.
Thank you