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 Adrian, the third dose should still be taken at the time you took your first dose – 48 hours after the first dose.
This will help to ensure there is enough PrEP in your body to prevent transmission.
As you were 12 hours late with this second dose, it cannot be said PrEP will still be as effective if taken at its recommended times. However some PrEP is still always better than no PrEP and the doses you have taken still makes this a low risk of transmission.
On-demand PrEP: https://i-base.info/guides/prep/on-demand
Hi,I took the first double dose Prep at 4pm and had sex at 11pm. Then I took the second dose not 24 but 40 hours after the first double dose. Should I take the 3rd dose 48hours after the first double as usual or take it 24hours after the late second dose?
Hi Sean, you have stated that you had sex on Sunday but have shown that you had sex Saturday at 4pm?
Being 45 minutes late with the 3rd dose is not going to have caused a problem. As long as you are within an hour of your normal time PrEP will still be effective.
On-demand PrEP is designed to have 2 subsequent doses after sex. This would include another dose of PrEP at 11:30pm on Monday. This is because usually on-demand PrEP assumes sex after the first dose, not the second.
Hi, I took on demand prep.
Thursday 11.30pm 2 doses
Friday 11.30pm 1 dose
Saturday Sex 4pm
Sunday 00.15am 1 dose
Sunday 11.30pm 1 dose (planned)
My sex was planned on Saturday but it actually happened on Saturday. The dose I took after my sex was 45 mins later. Will this be an issue？Thank you
Hi Evan, as you have mentioned this is probably best described as being on the verge of safe sex. This is because of the 8 hour delay on the last dose of PrEP.
However as you had ‘sort of’ taken a double dose of PrEP over the period of having sex, it is likely there was enough PrEP in your body stilla ctive to account for the delay in the last dose.
This would not be considered high risk given what PrEP you took and how you took it.
Hello everyone! My schedule was as follows: Friday 22:00 double dose. Saturday 22:00 single dose. 23:00 sex with positive undetectable man (as he stated). One hour later one more pill (improvising, just to be safe). Next dose Monday morning at 08:00, meaning 32 hours after the previous dose and not 24. I suppose I’m on the verge of safe? Thank you very much!
Hi ken, as you had used a condom there was no need to take PrEP.
Hi, I took on demand prep. However I was 6 hours late on my third dose, condom didn’t fail. Is it a cause for concern, do I need PEP? I was on time with my first and second dose.
Hi Martin, as your second dose was almost a day late and only taking the 3rd dose 8 hours after, PEP would be advised.
The initial double dose will provide some protection if you chose to not start PEP. Some PrEP is always better than none. As the first dose is a double dose, this can account for being late. Though it is not possible to say how much protection is given by being almost a day late.
I took a double dose of Prep at 6:30 pm, had unprotected sex about 6 hours later at 12 am, then didn’t take my second dose until 40 hours after my first dose, took my second dose 48 hours after my first dose. Should I consider taking PEP?