Prevent HIV with PrEP

What is PrEP?

PrEP, which stands for pre-exposure prophylaxis, is an effective way to prevent HIV. With PrEP, people who are HIV-negative take a pill (Truvada) once a day to reduce the risk of getting infected if they're exposed to HIV. PrEP is an additional method that is recommended to be used with other HIV prevention strategies such as condoms.

At this time, there is only one medication (Truvada) approved by the U.S. Food and Drug Administration (FDA) for PrEP. Truvada is a combination pill composed of two medications: tenofovir disoproxil fumarate and emtricitabine. Truvada is also used by people living with HIV, in combination with other medications, as an HIV treatment medication. 

Who is PrEP for?

PrEP is for people who are HIV-negative people and at risk for HIV infection. That can include people who have one or more partners who are living with HIV, people who have one or more partners whose status they don't know, men who have sex with men, trans* masculine people who have sex with men, trans* feminine people who have sex with men, people who have had sex without condoms, sex workers, people who use injection drugs, and other people who may be worried about HIV infection.

If you have sex and have difficulty using condoms or don't like to use condoms, PrEP is a way you can reduce your risk for HIV. For many people, PrEP reduces worry and anxiety around sex—enabling people to have healthier, safer sex lives. 

How do I get PrEP?

The medication used for PrEP is available with a prescription. You must be under a medical provider's care to access PrEP, since that provider will need to make sure it's safe for you to take PrEP. You might be able to access PrEP through your medical provider.

If you live in the San Francisco Bay Area, you may be able to access PrEP through the San Francisco AIDS Foundation PrEP Health Program.

If you live outside the San Francisco Bay Area, you can search for a PrEP provider in the U.S. here.

How effective is PrEP?

PrEP is very effective at preventing HIV infection. When used every day, it reduces the risk of HIV infection by up to 99%. When combined with other HIV prevention strategies, like condoms or treatment as prevention, there is even greater protection.

Now that PrEP has been available in community health centers for a few years, we've seen a few examples of clinics reporting zero new HIV infections among hundreds of clients taking PrEP. 

It is more important for transgender men, women and other people with vaginas to take PrEP every day as prescribed in order for it to offer full protection, since the drugs in PrEP reach lower levels in vaginal tissue than in rectal tissue.

It also takes longer for PrEP drug concentrations  to reach adequate levels for protection in vaginal tissue, so people having vaginal sex are advised that they will not be fully protected until after 20 days of daily dosing.

PrEP does not protect against sexually transmitted infections including gonorrhea, syphilis or chlamydia.

What are the side effects?

In clinical studies, the most common side effects people have reported for Truvada-based PrEP were stomach pain, headache, and loss of appetite. Oftentimes, these "start-up" symptoms are mild and go away after a month on treatment. Truvada is also associated with kidney problems in a small percentage of people, and small decreases in bone mineral density (bone strength) in some people. Studies show that decreases in bone strength are usually small, not associated with fractures or broken bones, and that bone density recovers after people stop PrEP.

Can I stop PrEP?

PrEP does not have to be a life-long medication. If you start taking PrEP, you need to take it every day for it to work. But, eventually, if you decide you don't want to be on PrEP anymore, you can discontinue PrEP under the supervision of your PrEP medical provider.

How can I afford PrEP?

Many people are able to access PrEP for free or low cost, by using their insurance benefits, patient assistance programs, or Medicaid. San Francisco AIDS Foundation PrEP benefits counselors help our PrEP clients figure out how to take advantage of insurance and other assistance programs to be able to afford PrEP.

Do I still need to use condoms on PrEP?

PrEP works well to prevent HIV, but it does not protect against other sexually transmitted infections like gonorrhea, chlamydia and syphilis. Using condoms can help protect against other sexually transmitted infections.

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