Although there's no cure for HIV, new HIV medications can help prevent the virus from taking hold inside your body. PrEP (pre-exposure prophylaxis) can lower your risk of getting HIV from sex by 99%. For years, the most common prevention method has been condoms. Newer methods, like PrEP, can lower your chance of infection if you're HIV-negative.
What Is PrEP? How Does It Work?
PrEP comes in two forms, a pill or injection. You start PrEP when you don't have HIV but are at high risk to get the virus because of sex or injection-drug use. It helps before you're infected, so HIV can't settle into your body and spread.
PrEP medicine options
PrEP medications to prevent HIV include:
- Truvada or Descovy, which are a combination of two medicines -- tenofovir and emtricitabine
- Cabotegravir extended-release injectable suspension (Apretude)
- Lenacapavir extended-release injection (Yeztugo)
The pill forms of PrEP are taken once a day, every day to prevent HIV from taking hold in your body. Apretude is taken as a shot once every eight weeks and Yeztugo is a shot you'll get twice a year.
How Effective Is It?
Skipping a dose or not taking PrEP regularly lowers your chance for the medicine to protect you. If you take the pill:
- Every day, your level of protection is around 99%
- Four days a week, your level of protection is around 96%
- Two days a week, your level of protection is around 76%
How well do PrEP injections work?
Given every two months, Apretude has been shown to be 90% effective in lowering the risk of HIV. After two doses, Yeztugo lowered HIV infection risk 100% in women and 96% in men.
How long does it take for PrEP to start working?
It can take seven to 20 days from when you take your first pill until it starts to protect you. That's because the medicine takes time to reach different tissues inside your body. Even if you decide on the long-term injections, you'll start with pills to get the medicine dose up inside your body before your first shot.
Is It Safe?
The first PrEP medication, Truvada, was approved by the FDA in 2012 and Descovy was approved in 2019. They may cause nausea, stomach upset, and dizziness. But these symptoms typically go away over time. Some people may also get pain or swelling from the injection.
None of the side effects have been life-threatening. Even after taking PrEP for five years, people haven't reported health problems because of it.
Are PrEP injections safe?
The long-term injections seems safe, in fact, Apretude was approved in late 2021. Side effects mainly include fatigue and headaches. Yeztugo was approved in 2025 and has similar side effects to Apretude.
You can't get HIV from taking PrEP because there's no HIV in it. It's also not a vaccine. PrEP doesn't seem to cause problems when you take it while you're using hormonal birth control, medication for depression, or alcohol and other party drugs.
What if I have kidney or bone trouble?
If you have kidney or bone problems, though, let your doctor know before you start taking PrEP medication.
We're still learning if PrEP later affects kids whose mothers used it during pregnancy and breastfeeding.
Could PrEP Work for Me?
It's a good option for someone in any of these situations:
- In an ongoing relationship with an HIV-positive partner
- Has sex with multiple partners and doesn't always use condoms
- Injects drugs or shares needles
What about pregnancy?
If you're wanting to get pregnant with an HIV-positive partner, ask your doctor about PrEP. It may be a way to lower the chances of you and your baby getting HIV.
PrEP and hormones
Research is still being done on the effects of taking PrEP when you're transgender and having hormone therapy. No bad reactions have been reported so far.
Will PrEP Work if I Might Already Have HIV?
For PrEP to protect you, you'll take the medicine before you come in contact with the virus. PrEP isn't a cure for HIV.
If you think you've been exposed, call your doctor right away or head to the emergency room. If you start taking a different kind of medication called PEP (post-exposure prophylaxis) within 72 hours, it can lower your odds of HIV infection.
If I'm Taking PrEP, Do I Still Need to Use Condoms?
PrEP can stop you from getting HIV, but it doesn't protect you from other sexually transmitted diseases like syphilis, chlamydia, and gonorrhea. You'll still need condoms for that. PrEP also doesn't prevent pregnancy.
Depending on the type of PrEP you take, you'll visit your doctor for an HIV test and follow-up care. While you're taking PrEP, you'll take an HIV test:
- Every three months for the daily pill
- Every eight weeks for Apretude
- Twice a year for Yeztugo
When Can I Stop Taking It?
It isn't a pill you have to take forever. You get to decide when to start and stop PrEP. Just remember that if you don't take it regularly, you aren't as protected.
Once you've started taking PrEP, you should stay on it for at least a month after you were last exposed to HIV.
If you think that you're no longer at risk of getting HIV, talk with your doctor before you stop taking PrEP.
Where Can I Get PrEP?
You need a prescription for it from any health care provider — doctor, nurse practitioner, or physician assistant — who is qualified. You might need to contact your local health department or a local AIDS organization to find someone who understands what it is and is comfortable writing the prescription for you.
You'll also need to get an HIV test first to make sure you don't already have the virus.
How Much Does It Cost?
PrEP can be expensive -- it can cost as much as $28,000 a year without insurance, depending on the brand. Most insurance plans do cover Truvada, which means you'd pay your normal copay amount for brand-name medications.
Coverage differs from state to state, but PrEP should also be covered by Medicaid and Medicare.
If you have to pay for PrEP yourself, there are financial assistance programs that may help, including from the drug manufacturer, public health services, and clinical trials.
