HIV is preventable. The tools available today, from daily pills to condoms to injectable medications, can reduce your risk of getting HIV by 80% to nearly 100%, depending on the method and how consistently you use it. Most people benefit from combining more than one strategy.
Condoms
Condoms remain one of the most accessible and widely used tools for preventing HIV. Consistent condom use during vaginal intercourse reduces HIV transmission by approximately 80%, based on a Cochrane systematic review of real-world studies. That number reflects how people actually use condoms, not perfect laboratory conditions, so correct use every time likely offers even greater protection.
External (male) condoms and internal (female) condoms both create a physical barrier that blocks the virus. They also protect against other sexually transmitted infections, which is a benefit that medications alone don’t provide. Water-based or silicone-based lubricant reduces the chance of a condom breaking. Oil-based lubricants like lotion or petroleum jelly weaken latex and should be avoided with latex condoms.
PrEP: Medication Before Exposure
Pre-exposure prophylaxis (PrEP) is a prescription medication taken by HIV-negative people to prevent infection. It’s one of the most effective prevention tools available, and there are three forms to choose from.
Daily Oral PrEP
Two pills are approved for daily use. Truvada is approved for anyone at risk through sex or injection drug use. Descovy is approved for people at risk through sex, but it has not been studied in people assigned female at birth who could acquire HIV through receptive vaginal sex. When taken consistently every day, oral PrEP reduces HIV risk by about 99% during sex.
On-Demand PrEP
For men who have sex with men and don’t have sex every day, an “on-demand” dosing schedule called 2-1-1 is an option. You take two pills 2 to 24 hours before sex, one pill 24 hours after that first dose, and one more pill 24 hours later. This approach has been studied specifically in men who have sex with men and is not recommended for other populations.
Injectable PrEP
A long-acting injectable form of PrEP is given as a shot every two months after two initial monthly doses. In clinical trials, HIV infection occurred in 0.57% of people receiving the injectable compared to 1.7% of those taking daily oral PrEP, making the injectable roughly three times more effective. Much of that gap comes down to adherence: it’s easier to show up for a shot every two months than to remember a pill every day.
PrEP requires a prescription and regular follow-up visits, typically every three months, which include HIV testing and kidney function checks. Most insurance plans and state assistance programs cover PrEP at no cost.
PEP: Medication After Exposure
Post-exposure prophylaxis (PEP) is an emergency option for people who may have been exposed to HIV through sex, needle sharing, or sexual assault. PEP must be started within 72 hours of the possible exposure, and sooner is better. You take the medications every day for 28 days.
PEP is not meant to replace ongoing prevention strategies. Think of it as a backup plan. If you find yourself needing PEP more than once, that’s a strong signal that daily PrEP would be a better fit.
Treatment as Prevention
If your sexual partner is living with HIV, their treatment status matters enormously. A person with HIV who takes antiretroviral therapy and maintains an undetectable viral load has zero risk of transmitting HIV to sexual partners. This concept, known as Undetectable = Untransmittable (U=U), is backed by large studies tracking thousands of couples over years without a single linked transmission.
This means that effective HIV treatment is also effective HIV prevention. If your partner is on treatment and their viral load is consistently undetectable, sex without a condom does not carry a risk of HIV transmission. An undetectable viral load is confirmed through routine blood tests, so the key factor is that your partner stays on treatment and continues regular monitoring.
Safer Injection Practices
Sharing needles, syringes, or other injection equipment is one of the most efficient ways HIV spreads. If you inject drugs, using a new, sterile syringe every time is the single most important thing you can do to prevent HIV.
Syringe services programs (sometimes called needle exchanges) provide free sterile equipment and safe disposal. These programs are associated with a roughly 50% reduction in new HIV and hepatitis C infections. People who use syringe services are also five times more likely to enter drug treatment and three times more likely to stop injecting. These programs exist in most major cities and many smaller communities.
Daily oral PrEP with Truvada is also approved for people at risk through injection drug use, adding another layer of protection.
Male Circumcision
Voluntary medical male circumcision reduces the risk of female-to-male HIV transmission by approximately 60%. This effect has been demonstrated in large clinical trials conducted in sub-Saharan Africa, where heterosexual transmission drives most new infections. The protection is partial and works in one direction (protecting the circumcised male partner), so it’s best combined with other methods like condoms or PrEP rather than relied on alone.
Preventing Transmission During Pregnancy
Without any intervention, an HIV-positive mother has a 15% to 45% chance of transmitting HIV to her baby during pregnancy, labor, delivery, or breastfeeding. With proper antiretroviral treatment throughout pregnancy and delivery, that risk drops to below 1%. This is why HIV testing is a standard part of prenatal care.
Countries that have scaled up treatment for pregnant women living with HIV have shown that virtual elimination of mother-to-child transmission is achievable. If you’re pregnant or planning to become pregnant and either you or your partner is living with HIV, starting or continuing treatment early is critical.
Regular Testing
Prevention works best when you know your status. The CDC recommends that everyone between ages 13 and 64 get tested for HIV at least once in their lifetime as part of routine healthcare. If you have ongoing risk factors, such as multiple sexual partners, a partner living with HIV, or shared injection equipment, testing every 3 to 6 months is appropriate.
Rapid tests and home testing kits can return results in 20 minutes. Early detection matters not just for your own health but for prevention: the sooner someone starts treatment and reaches an undetectable viral load, the sooner they can no longer transmit the virus to others.
Combining Methods for Stronger Protection
No single method needs to carry all the weight. The most effective approach is layering strategies that fit your life. Someone in a relationship with an HIV-positive partner might rely on their partner’s undetectable viral load plus their own PrEP. A person who injects drugs might combine sterile syringes with daily oral PrEP. Someone with occasional risk might keep condoms on hand and know where to access PEP if something unexpected happens.
The best prevention plan is one you can actually stick with. If daily pills feel like a burden, the injectable PrEP shot every two months might work better. If you’re not in a position to access PrEP, consistent condom use still cuts your risk substantially. What matters most is choosing the combination that fits your circumstances and using it consistently.