Question
Late with the after sex on-demand PrEP dose.
5 March 2022. Related: Adherence, All topics, PrEP.
Hello for all. I started 2-1-1 prep, took 2 pills 3 hours before sex. Then I took second pill after 24 hours after sex, not 24 hours after the first 2 pills – I have delayed the second pill by 3 hours. I’m still continuing taking PrEP every day because I have sex but I am just worrying is it ok to delay the second dose by 3 hours? Thank you for reply.
Answer
Hi, how are you doing?
Being 3 hours late on the second dose is not likely to cause a problem. The initial double dose will have increased the drug levels within your body more than a single dose anyway. These drugs tend to remain at the required drug level within the body for more than 24 hours.
While it is best to take the medication as routinely as you can, being late by 3 hours is unlikely to cause you any problem. As you have now continued with daily dosing, PrEP will have remained at effective level within your body.
There is no reason to be concerned after this event,
Josh.
Hi Thomas, after 7 days PrEP would be effective. As long as you continue with PrEP for a minimum of 2 days after this encounter there is no risk.
I had unprotected vaginal sex on the day 8 of prep l was taking single dose each day was it too early or l should’ve waited for 21 days and so what can l do now
Hi Mikyle, as you had taken an initial double dose of PrEP your doctor is right in that you do not need to be on PEP. The 7 day requirement is only needed when taking a single pill each day.
As you have then continued taking PrEP from this day there is no risk from this exposure. You need to take PrEP for 2 days AFTER sex for the on-demand dosing to work.
Hi I didnt know the persons status unfortunately I trusted too easily and I was ghosted and he claims his straight I was just an experiment bare in mind it was my first time, so much regret for not waiting.
I had an issue with the dosing too, doctor said he wasn’t going to put me on PEP (it was still during the 72hr window) because I was already on prep but I haven’t done the full 7 pills prior my encounter.
Day 1: took first 2 pill dose 24hrs to +-28hrs before the deed, I ended up not having intercourse on the day I took the first dose of 2 pills
Day2: 24hrs later and didnt have intercourse yet I decided to continue taking 1 pill and continue from there on. This day I had intercourse.. a little bit over the 24hrs and another pill that morning so a total of 3 pills had been in my system.
Day3: I took another pill and still continuing 1 per day rather.
He didn’t climax inside of me but I done my research on pre-ejaculation fluid because it had been unprotected and I was stressed either way and ended up going to the doctor.
Would there have been some form of protection? All based on not knowing his status.. he said his negative but anyone can say that.
Hi Alex, as you had taken 2 days of double dosing you are likely protected and PEP is not needed.
As you did not take PrEP on-demand as recommended it cannot be guaranteed that it will have the same effectiveness, but the PrEP you did take will still lead to this encounter being low risk. Because of this PEP is not needed.
The additional double dose you had taken will have kept the levels of PrEP in your body high which can account for being late with the dose after sex.
The vomiting you had on day 3 is not worrying. As it was more than 2 hours after your dose of PrEP, your body will have absorbed PrEP and you would not have vomited any of it.
Hey! I messed up the Prep timing a bit.
Day 1 – I took a double dose at 4pm
Day 2 – as I didn’t have sex the previous day I took another double dose at 4pm
Day 2 – that day I had sex around 7pm
Day 3 – I forgot to take the single dose at the right time and took it only at 2:30am (10.5h late)
Day 4 – I will take my next dose at 4pm and planning to continue for 2 more days.
I also threw up in the morning of Day 3 but not sure it’s anything to worry about as it was quite a while after the previous dose?
Do I need PEP? Do I need clinic advice?
Thanks!
Hi, to clarify you took the first double dose on the first dose, the second dose on the the third day at 2:12pm and then the third dose at 11:21pm on the third day?
As mentioned this means you were 15 hours late with this second dose. What time did you have sex on the day that you took the first dose?
Taking this course of PrEP will provide some protection but it will not be the same as taking it when on time. Some PrEP will always be better than no PrEP.
As you had taken the first double dose, this higher concentration of PrEP than a regular dose will help to account for being late with your second dose. Was this a risky exposure of HIV?
Risk of HIV is explained here: https://i-base.info/guides/testing/risks-for-transmission
I took the double initial dose of prep at 11:21pm, then forgot to take it the next night, so I ended up taking it at around 2:12pm when I woke up third day my second dose would be 15 hours late then I took my third dose at the apporiate time of 11:21pm hours after the second dose. Is that ok?
Hi Pablo, as your partner has stated that they are undetectable there is no risk of transmission. This is called U=U: https://i-base.info/u-equals-u/
Taking PrEP 4 hours before is in the recommended time window for protection when using on-demand PrEP. As long as you take the first dose between 2 and 24 hours before you have sex PrEP will be effective. You do not need to continue taking PrEP continuously. For full protection you can stop after the second day after you had sex (3 doses in total).
On-demand examples: https://i-base.info/guides/prep/real-life-examples-for-on-demand-dosing
Hello, I had sex with a man who claims to be undetectable but my concern is that I only took it 4 hours before having sex with him, after learning that he was supposedly undetectable I have decided to take the prep continuously. (I obviously took the other two pills respectively). How much risk is there knowing that I only took it 4 hours before having sex with him? I am very worried, I will go for a test after three weeks from now to be sure of the result.