Using PrEP After Being Bred

[downtownswallow]

Curious re how effective it is to take PrEP after being bred.  How soon after is soon enough?  How much should you take?

[BootmanLA]

7 hours ago, downtownswallow said:

Curious re how effective it is to take PrEP after being bred.  How soon after is soon enough?  How much should you take?

1. If you take it AFTER being bred, it's no longer PrEP. PrEP stands for PRE-exposure prophylaxis, and "PRE" means "Before".

2. There is such a thing as PEP - Post-exposure prophylaxis. Conceptually, it's like the morning-after pill for women; if taken soon enough after exposure to HIV, it can help ward off infection. The dosage is set by the prescribing medical professional. My understanding is that there is a large dose taken up front (kind of like PrEP on demand), followed by 28 days of daily dosing. This is not something you want to self-dose or self-medicate with; it's a case of "get to an emergency room or urgent care (or local health unit clinic, if there is one) ASAP" and let them prescribe for you.

3. It is NOT guaranteed prevention against infection and is intended for emergency use only, for cases where someone was exposed  to HIV accidentally (condom failure, needle stick, sexual assault, etc.).

4. The CDC says that you must being PEP within 72 hours for it to be effective (and again, it is not guaranteed to work, depending on the viral load, how much was received, how long before PEP treatment was started, etc.). 

[Guest]

On 10/30/2021 at 1:57 AM, BootmanLA said:

4. The CDC says that you must being PEP within 72 hours for it to be effective (and again, it is not guaranteed to work, depending on the viral load, how much was received, how long before PEP treatment was started, etc.). 

One thing I'd like to add is that the sooner after exposure someone starts with PEP, the higher the chance for succes.

[Chipaleale]

Not necessarily "after", but if you are not a regular daily PreP user you can use the 2-1-1 method and still get effective prevention.  Take 2 pills between 1 and 24 hours before sex, then 1 every 24 hours after the first dose for at least 2 more days.  Or keep taking 1 per day if you want to continue prevention for more breedings.  I would guess the protection between doing this 1 hour before vs 1 hour after sex would be similar, but don't see any studies on it.

Google prep 2-1-1 or [think before following links] [think before following links] https://www.cdc.gov/hiv/basics/prep/on-demand-prep.html

Edited November 8, 2021 by Chipaleale

[tj87]

PreP medicines such as Truvada require a steady dose before sex, so that it can build up in your system to prevent HIV infection. It must be used before and after sex to maintain sufficient levels in the blood stream to prevent the HIV virus from replicating and causing HIV.

The ideal regime is:
7x doses, once per day ahead of bareback sex and 2 doses (once per day) after bareback sex.

Event based dosing, which may be less effective is:
1x Double-dose 24-hours ahead of bareback sex and 2 doses (once per day( after bareback sex.
There is some wiggle room on the 24 hours but no less than 2 hours.

There are other dosing methods but all require the medication in your system prior to sex.

Anything less than this - i.e. PreP taken after sex with a detectible HIV+ person will not allow sufficient levels of the medicine to build up in the body and prevent HIV from taking hold.

PEP - as mentioned here - is post-exposure medication.
It is a combination of Truvada and another powerful antiretroviral. It is a month long course of pills and it has proven successful in preventing HIV from replicating and causing HIV. I've taken PEP myself, once, and I lost 10lbs in a month with no other change to diet or exercise regime... the drugs take a toll.

The Bottom Line:
PreP taken on its own and only after sex with a detectible person will not be effective in preventing HIV transmission.

If you are worried about a recent sexual encounter and inside the 48 hour window for PEP to be effective, I urge you to contact a local sexual health clinic to get on a course of PEP.