PrEP (pre-exposure prophylaxis) is the use of the HIV medication Truvada by an HIV negative person to prevent HIV transmission. With Health Canada's approval of Truvada for this purpose in February 2016, the drug will likely soon become more widely available to HIV-negative people (it was previously used only to treat HIV).
At the time this article was published, the daily use of oral Truvada is the only type of PrEP that has been found to be effective in multiple studies. However, other forms of PrEP are being investigated and may become available in the future.
How well does it work?
PrEP has been called a game-changer because it can drastically decrease the chance of HIV transmission during sex. When taken correctly and consistently, Truvada is a highly effective HIV prevention strategy. If it is taken every day and used with treatment as prevention or condoms, the chance of transmission is reduced even further.
What happens if someone forgets doses?
If a person forgets to take their PrEP pills, the chances of transmission increase. Also, Truvada is not effective against strains of HIV that are resistant to Truvada. For example, a Canadian man who was taking PrEP religiously became HIV positive with a drug-resistant strain of the virus.
While PrEP is a highly effective strategy for preventing HIV, it does not work against other sexually transmitted infections (STIs). It is therefore recommended that PrEP be used along with condoms.
Who can take PrEP?
- PrEP should only be taken by people who are HIV-negative and at high risk for HIV -- for example, people whose sex partners are HIV-positive and have a detectable viral load or people who have condomless sex with partners of unknown HIV status. (If an HIV-positive person takes Truvada without other HIV drugs, they could develop a drug-resistant strain of the virus.)
- PrEP should only be taken by someone who has a prescription and sees a healthcare provider regularly (at least every three months).
Why is it important to see a doctor regularly?
Guidelines recommend that a person on PrEP see a healthcare provider regularly to check in about taking the medication on schedule and for risk-reduction counselling, as well as regular HIV and STI testing. The healthcare provider can also work with PrEP users to keep an eye out for possible side effects and drug toxicity.
Is the cost covered?
Only Quebec's provincial health plan currently covers the cost of Truvada for PrEP. People with workplace drug plans may have access to PrEP through their private insurance (check with your provider). Status First Nations people and Inuit are already covered under the Non-Insured Health Benefits (NIHB) Program.