If you’re HIV-negative but in a high-risk group for HIV, ask your doctor about preexposure prophylaxis, or PrEP. This consists of taking medication to reduce your risk of HIV prior to becoming infected, and it’s been shown to be highly effective when taken consistently. PrEP should be considered, for instance, if you’re HIV-negative, but in a relationship with an HIV-positive partner, or if you have multiple sexual partners and don’t routinely use condoms.
PrEP is available in both pill form and as injections.
Truvada and Descovy are both pills that combine the medicines emtricitabine and tenofovir. When taken every day as directed, they have been found to be 99 percent effective in preventing sexual transmission of HIV and significantly reducing your risk of getting HIV. It can be difficult, though, for some people to stick to a daily regimen.
In December 2021, the U.S. Food and Drug Administration (FDA) approved the injectable PrEP drug cabotegravir (Apretude), which is administered once every two months. In clinical trials, Apretude was shown to reduce the risk of contracting HIV by 69 percent for cisgender men and transgender women who have sex with men compared with taking the daily PrEP medication. For cisgender women at high risk for HIV, the injection reduced the risk of contracting the virus by 90 percent compared with treatment with daily oral medication.
A course of antiretroviral medicines (ART) after you’ve potentially been exposed to HIV can also prevent you from becoming infected; this is called postexposure prophylaxis (PEP). If you’re worried you’ve been exposed to HIV, contact your doctor as soon as possible or go to the emergency room. PEP needs to be started within 72 hours to work, but the sooner the better. Every hour counts, according to the CDC.
If you’re HIV-positive, taking ART as directed decreases the amount of the virus in your body — what’s known as viral suppression. Sometimes the viral load is so low that even HIV tests don’t detect it. Being virally suppressed or having an undetectable viral load helps prevent the spread of HIV and is known as “treatment as prevention.”
Those living with HIV who maintain an undetectable viral load have effectively no risk of transmitting the virus to their sexual partners, according to the CDC. For pregnant women living with HIV, treatment as prevention (when HIV medicine is taken throughout pregnancy, labor, and delivery, and if preventive medicine is given to the baby for several weeks after delivery) can reduce the risk of transmission to 1 percent or less.