The World Health Organization (WHO) recommends two PrEP regimens: daily (one pill per day), as well as “on demand”, where you take 2 PrEP pills 12 hours before sex, and then take one pill 24 and 48 hours after potentially risky sex. It is very important to take PrEP in the two days after sex, so that the concentration of the drug needed for prevention remains in the body.
On demand intake:
If, when using the “on demand” regimen, you have sex on the second day after starting PrEP, then you need to continue taking the drug for another 2 days.
Both regimens have been shown to be effective, although the “on demand” regimen was only studied among men who have sex with men.
If you choose to take PrEP daily, then it is important not to forget to take the prophylaxis drug at the same time. If it was not possible to take the pill at a specific time, you need to do so as soon as it is possible, and from the next day to use the established dosing schedule. There are a lot of ways to help you to remember to take PrEP. You can “tie” this to some daily and familiar event, like breakfast or dinner, bathing, jogging, brushing your teeth, etc. You can also install a special application on your smartphone, which will remind you to take your pill.
There are no strict recommendations in terms of taking PrEP with other medications or food. However, if you suffer side effects, like nausea or diarrhea, doctors recommend taking the drug with meals in order to prevent such side effects. During research, interactions between PrEP and alcohol and recreational drugs were not observed. The drug can be taken with sex hormones and non-prescription drugs.
The level of risk of HIV infection may vary. You need PrEP if you have an active sex life with various partners, whose HIV statuses you are uncertain of. Later, if you will build sincere and monogamous relations with an HIV-negative partner and will regularly test on HIV along with your partner, you can just stop taking PrEP.