The most effective way to prevent HIV is to take PrEP every day.
Using PrEP “on-demand” may lower the risk of HIV in people who have anal sex. “On demand” means using PrEP only around the time of sex. In the best study of on-demand PrEP, most people were having sex often. This might have made on-demand PrEP seem more effective than it is.
Most people who were studied identified as male, and had male sexual partners.
No medications are approved by Health Canada to be used on-demand for HIV PrEP.
On-demand PrEP should only be considered for anal sex. It should not be used by people who have vaginal or frontal sex, or by people who share drug equipment. On-demand PrEP is not recommended for people with active hepatitis B infections.
HOW TO TAKE PrEP ON-DEMAND:
If you know that you might have anal sex without a condom:
· Take 2 tenofovir DF/emtricitabine 300 / 200 mg (Truvada) pills 2 – 24 hours before sex
· AND take 1 tenofovir DF/emtricitabine 300 / 200 mg (Truvada) pill every 24 hours until you have 2 sex-free days
FOLLOW UP WITH YOUR HEALTH CARE PROVIDER EVERY 3 MONTHS FOR ONGOING HIV TESTING AND MONITORING.