PRep, how long before/after possible contact with virus?

[Andrew88]

Hi!

I'm a male heterosexual(sometimes bi) who travel and work a lot in quite high risk African countries. Originally I'm from a Scandinavian country. I just came home from Tanzania after a 3 months stay there. I was suppose to stay for 1 month, but had to expand the stay so I brought to few condoms. I'm also latex intolerant, which complicates the matter of getting them locally.

Truvada is quite easy to get there, so after getting a regular partner, I decided to go for PRep just to be sure(I didn't trust her 100%). I've been taking Truvada since the end of Jan(adherence 100%) and still take them up to now. I'm back in Norway now and my last sexual encounter was around 9 days ago. After returning I've been to the STD clinic for full screening, and tried to get some more info around PRep. But since PRep is not approved here in my country, all they said was "no comment".

My questions therefore is; How long should I remain on PRep just to be sure? I read someplaces that 2 days after possible contact should be enough, while some other guidelines say 30 days. I have no sideeffects from Truvada, but since I can't get PRep in my country I want to save as many pills as possible for a rainy day.

Also, I've read that it takes around 7 days to achieve full protection of the rectal area and something like 20 days for the vaginal area. But I've found no information how long it will take for the insertive part to reach full protection in the penile area.
This goes for both anal and vaginal sex, but always as the insertive part, as I don't like being the bottom.

I tried googling and asking at my local clinic, but found no good answers so far.
I would be very grateful if someone from this community could enlighten me a bit on the subject.

[Jim Allen]

Hi

So starting Truvada as PrEP for men it takes about 7 days to reach high effective levels.  And staying on Truvada for four weeks after the last potential exposure is recommended. Also you should be tested for STI's and HIV before starting PrEP and at regular intervals after starting.

Remember some sexual practices which may be described as ‘safe’ in terms of HIV transmission might still pose a risk for transmission of other STI's. So please do get fully tested regularly for all STI's including HIV and more frequently if unprotected intercourse occurs. Also note that it is possible to have an STI and show no signs or symptoms and the only way of knowing is by testing.

You can read more on PrEP and Prevention here:

HIV 101 - HIV prevention
HIV prevention

HIV PEP and PrEP
PEP and PrEP

PrEP Reaches Top Effectiveness After a Week of Daily Dosing
PrEP Effectiveness

PrEP 101 - Questions and Answers
PrEP Q&A

Jim