HIV PrEP & prevention

What is PrEP?

PrEP stands for Pre-Exposure Prophylaxis. It is an evidence-based medication—available as a daily pill or periodic injection—designed for individuals who do not have HIV to significantly reduce their risk of acquiring it. When taken consistently as prescribed, PrEP is extremely effective, reducing the risk of getting HIV from sex by up to 99% and from injection drug use by over 74%.

How does PrEP protect a person from getting HIV?

PrEP works through antiretroviral medications that target key enzymes HIV needs to replicate inside the immune systems cells. If you are exposed to HIV, these active drug compounds block the virus from copying itself, preventing it from establishing a permanent infection or spreading throughout your body. It acts like an internal shield: as long as there is enough medication circulating in your tissues, the virus cannot take root.

When does PrEP become fully effective after starting to take it?

• The timeline for full protection depends on the type of sexual activity or exposure:
• Receptive anal sex: Daily oral PrEP reaches maximum, peak protection at around 7 days of consecutive daily use.
• Receptive vaginal sex and injection drug use: The medication takes longer to build up to protective levels in those specific tissues, reaching maximum effectiveness after about 21 days of daily use.