Young white man talking to a doctor

Is PrEP right for you?

Clinically reviewed and updated by Nancy Kupka, PhD, RN Oct 16, 2022 • 5 min

Even though people living with HIV are now enjoying long, healthy lives, you still want to do whatever you can to protect yourself against the virus. If you're someone who engages in sex with multiple partners, has a partner with HIV, or shares needles or syringes, PrEP is something you may want to consider after consulting with your provider.

Here's what you need to know.

What is PrEP?

PrEP stands for pre-exposure prophylaxis. It is a pill you take that may help prevent you from contracting HIV.

How does PrEP prevent HIV?

PrEP doesn't work the same way that vaccines work. Instead of preparing your body to combat a particular disease, PrEP medication lives in your bloodstream, helping to prevent HIV from taking hold in your cells.

Here's how it works: When taken every day, the medication blocks an enzyme called HIV reverse transcriptase. When this enzyme is blocked, the virus cannot make more copies of itself in your body, and therefore can't spread.

Do you have to take PrEP every day to prevent HIV?

It's important to take PrEP as it is prescribed by your provider. Talk to your provider about the most effective way to take PrEP to help protect against HIV.

How effective is PrEP?

When it's taken correctly, PrEP is about 99% effective for preventing the sexual transmission of HIV. It's about 74% effective for preventing HIV transmission through injected drugs and needle sharing.

Is it possible to get HIV while taking PrEP?

Because PrEP isn't 100% effective, there is still a risk of getting HIV while taking PrEP. However, the biggest barrier to effectiveness is not taking PrEP as prescribed. If you are taking PrEP as prescribed by your provider, it may dramatically decrease your risk of contracting HIV.

How long does it take for PrEP to be effective?

Depending on your individual circumstances, it may take up to 21 days for PrEP to be maximally effective. Don't forget to ask your healthcare provider about the most appropriate window for you personally.

Does PrEP have any side effects?

In some people, PrEP has some mild side effects, including nausea, diarrhea, headache, fatigue and stomach pain. However, these side effects generally go away over time. No significant negative health effects have been observed in people taking PrEP.

Do I still need to use condoms while taking PrEP?

Yes, you still need to use condoms while taking PrEP. PrEP isn’t 100% effective and doesn't protect against other sexually transmitted infections (STIs). Studies have shown that latex condoms provide an effective barrier against even the smallest STI pathogens.

How do I get PrEP?

You'll need to talk to a healthcare provider to get PrEP, since it requires a prescription. Your provider will need to test you for HIV, as well as do a health screening to make sure PrEP is the right fit for you. You can make an appointment with your provider, talk to an HIV-trained pharmacist at your local Walgreens, or visit a health clinic like Planned Parenthood to get started on your PrEP journey.

How Walgreens can help

If you've gotten a prescription from your healthcare provider, it's time to head to your local Walgreens. We can fill your prescription for you. If you don't have health insurance, we can also help you get PrEP for free. We've partnered with the Department of Health and Human Services on the Ready, Set, PrEP program. To qualify for the program, you must be HIV-negative, have no drug coverage, and hold a valid prescription for PrEP. You can learn more about the HHS's Ready, Set, PrEP Program by visiting or calling HHS at 855-447-8410.

Published October 2020. Clinically reviewed and updated by Nancy Kupka PhD, RN, October 2022.

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