PrEP to Prevent HIV

Human immunodeficiency virus (HIV) is a virus that weakens your immune system, making it harder for your body to fight off certain infections and diseases. HIV is passed from one person to another through body fluids. Although there is no vaccine or effective cure for HIV, there are ways to control the virus to protect yourself and others.

What is PrEP?

Pre-exposure prophylaxis (PrEP) is a method whereby a person at high risk for HIV takes an antiviral medication to prevent contracting the virus. When taken everyday, PrEP has been shown to be up to 99% effective at reducing the risk of getting HIV.  Currently in Canada, the recommended regimen is a combination pill containing two antiviral drugs, tenofovir and emtricitabine. They work together to disrupt the replication of the virus within the body’s immune system to prevent a permanent infection.

PrEP is most effective when taken daily, but in certain individuals, it may be taken on-demand as two pills before sexual activity followed by one pill daily for 48 hours. Speak with a healthcare professional to learn more about this alternative.

Should I take PrEP?

PrEP may be considered if you are HIV-negative with an ongoing risk for acquiring HIV and:

  • Have an HIV-positive partner with a detectable viral load
  • Sometimes have condom-less intercourse and don’t know the current HIV status of one or more of your partners
  • Sometimes use injection drugs and share needles

Is PrEP safe?

PrEP is safe and usually well tolerated. Most people taking it report no serious side effects. Some may experience nausea, diarrhea, headache or dizziness. These effects are generally mild and go away over time. However, the long-term effects of taking PrEP are not known. 

How do I get PrEP?

PrEP requires a prescription from a physician or nurse practitioner. You should find a healthcare professional with whom you feel comfortable talking about your sexual behaviours and drug use. Local sexual health clinics would also be able to connect you with healthcare providers experienced with prescribing PrEP. Once you start PrEP, regular three-month clinic visits will be necessary for ongoing testing and monitoring.

The cost of PrEP can be quite expensive, but it is covered by most public and private plans and there are lower-cost generic options available. For more information about coverage, ask your pharmacist or healthcare professional or visit your local sexual health clinic.

What else can I do to prevent HIV?

  • Get tested regularly for sexually transmitted diseases (STDs), including HIV, and encourage your partners to do the same.
  • Use condoms during intercourse. When used correctly, condoms are highly effective at preventing HIV and other STDs.
  • If you use injection drugs, avoid sharing needles with others.

Speak to your pharmacist or any other healthcare provider if you are interested in PrEP. More information on HIV and PrEP is available on the Canadian AIDS Treatment Information Exchange (CATIE) website here:

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