Question
Can I separate the double dose when using 2:1:1 dosing for PrEP?
28 December 2025. Related: Adherence, All topics, PrEP.
Hi friends,
I am a man and I sometimes I take 2:1:1 PrEP on demand. But I did not take the initial two pills at the same time because doing so causes me to vomit. Instead, I spaced them a few hours apart — I took one pill at 5 p.m., another at 8 p.m., and had sex at around midnight. I have tested negative several times using rapid test kits.
But until today I learnt that one must/d better take initial two pills together for 211 doese. I’m very worried because, on several occasions when I used the 2-1-1 regimen, I did not take the initial two pills at the same time.
Should I be worried about it or does it mean I’d better only take Prep on daily basis in future?
I look forward to your reply very much and wish you a Merry Christmas in advance.
Answer
Hi there
Please do not worry about this.
2:1:1 dosing is very effective ways for men to take PrEP.
Recent UK guidelines in 2025 also say that it is okay to separate the two pills in the initial double dose.
This can really help if you find taking both doses at the same time is difficult. For example, this can reduc any mild side effects from taking the double dose at the same time.
The main thing is to make sure that both doses are taken within a few hours of each other – and both need to be 24 to 2 hours before you have sex.
This guide has more info:
best wishes for the holidays too :)
Hi Mark and thanks for getting in touch.
I would start with a double dose for an extra layer of protection but you are safe to start with a single dose as well
Hi sorry if this is the wrong post to comment on im looking for advice on dosage?
If i took a double dose sunday followed by a single dose monday when sex occured however it was protected, i then missed my third dose on tuesday by accident, if I was to continue now with any unprotected sex as its been two days now since my last dose should i start again with a double dose?
Thanks