Is it 100% safe?
It is also known as “intermittent,” “non-daily,” “event-driven,” or “off-label” PrEP use. The type of “on-demand” PrEP that has been studied is the “2-1-1” schedule. This means taking 2 pills 2-24 hours before sex, 1 pill 24 hours after the first dose, and 1 pill 24 hours after the second dose.