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How does PrEP work?

I want you to think about building a wall of protection. Each of these blue pills, like a blue brick we’re building a blue wall to protect ourselves from HIV. So, if I lay down one brick do I have a wall? With this medication you need to take it on an ongoing basis so, one day is one brick, second brick, third brick. Do you see your wall is getting built? And I skip a brick. And then I lay a brick and I lay a brick and I skip another brick and another brick. What happens to your wall? You don’t have to be an architect for me to say that, that wall is not as strong. If you’re having anal sex, you need seven bricks to create that wall of protection. If you’re having vaginal sex you actually need 21 days of protection. So that’s why taking this on a daily basis is so important. Because you want to maintain a really strong wall of protection.

Dr. Flash explains the science behind how PrEP protects you from HIV.

PrEP blocks HIV from taking hold in the body and consistent, daily use is associated with increased protection.

Click here for more information on PrEP.


#AskTheHIVDoc is a video series from Greater Than HIV featuring top HIV doctors providing answers to commonly-asked questions about HIV prevention, testing and treatment.

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