How PrEP (Truvada / Descovy) for HIV Works

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Pre-exposure prophylaxis (or PrEP) is medicine taken to prevent an HIV infection. When taken as prescribed PrEP reduces the risk of getting HIV from sex by about 99% & from injection drug use by at least 74%.

Gilead, the manufacturer of PrEP, also has a medication co-pay program that may allow you to get access to this medication free of charge. Use the link to learn more:

[thomasmcnamee]

It is so important to know that if PREP does not work even though you are taking it. And continue to take after acquiring HIV. This can significantly reduce the effectiveness of whatever HIV medication your DR puts you on. The longer you stay on PREP after getting HIV will determine how long and in some cases, if ever will you be undetectable. So if you are on PREP and having regular sex with different partners especially unprotected I suggest getting tested every four to six weeks.

[Marcoification]

Thank you, great information! I was wondering if taking the medication at different hour every day can make you vulnerable and make the pill to fail preventing getting HIV? I have been taking the medication for about 2 months now but I have had inconsistency taking it at a specific hour… i do take it every day though and I haven’t missed a day since day 1 taking it. Would like to know .. thanks !

[anthonyn.]

How far we have come in almost 30 years.

[thigarette]

hi can you clarify on the injection? i'm currently on apretude and it's on a 2month schedule, the 1 month is only for the onboarding. does apretude still have sufficient efficacy for preventing hiv every 2 months?

[andyanderson]

Are the T Cells still able to function as normal with the Prep Barrier around them? do they still attack invaders and kill foreign pathogens the same ?

[andyanderson]

it used to be 99% chance of not getting it, now it's 92%...oops? resistance maybe?- also can you CD4 cells operate normally with a coating around them?

[debchancy]

my primary care doc who I have been going to for years in my backward conservative community has not a clue that I am gay and I would never be the person I would go to for this.

[AmitKumar-hywo]

40 seconds after intercourse while removing my condom, some veginal fluids touches my hand and then I touched my penis head ( glans) all this within 40 sec, now I want to know that what are the chances of HIV transmission if my penis is uncirmcise.and the other person was hiv positive.

Hiv transmission chances % :-????

Other STD chances %:- ????


Please answer specific to hiv sir

[pegibbons]

Why do you say 92%


How many people who have taken PREP religiously.... had a breakthrough infection?