To be effective at preventing HIV, PrEP must be taken every day as prescribed by your doctor. If you miss one dose, that’s okay. Take your next dose as planned. If you miss two or three doses while you’re sexually active, or if you don’t take PrEP as prescribed, check in with your doctor to make sure that you’re still HIV-negative. You can restart your PrEP routine after you get a new negative HIV test.
Data analysis from the iPrEx study found PrEP to be effective:
- For people who take 7 PrEP pills per week, their estimated level of protection is 99%.
- For people who take 4 PrEP pills per week, their estimated level of protection is 96%.
- For people who take 2 PrEP pills per week, their estimated level of protection is 76%.
