Man using laptop to look up information on PrEP for HIV prevention

PrEP for HIV prevention: how it works and more

Written on May 22, 2023 by Sendra Yang, PharmD, MBA. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Table of contents

In the early 1980s, a new infection was discovered, later identified as HIV.[1] In the United States, the Center for Disease Control and Prevention (CDC) had a historic and integral part in public health efforts to address HIV infection.[1] Approximately 1.2 million people in the United States had HIV in 2019, though not all knew they had the infection.[2] An estimated 87% of these individuals had knowledge they were HIV-positive.[2] Every year, more than 30,000 Americans are diagnosed with HIV.[2,3]

Currently, there is no cure for HIV. Once you get it, you will have it for your entire life.[3,4] Without proper treatment, HIV can lead to acquired immunodeficiency syndrome (AIDS). However, HIV can be controlled with appropriate treatment and medical care. You can also use various strategies to limit your risk and prevent HIV infection.

More about HIV

Human immunodeficiency virus, or HIV, is a virus that attacks your body's cells and damages your immune system.[3,4] HIV can be passed from person to person through infected semen, vaginal fluids, anal mucus, blood, and breast milk.[3,4] Methods of HIV transmission include [3,4]:

  • Engaging in vaginal or anal sex with someone infected with HIV
  • Sharing of infected needles or syringes
  • Getting stuck with an HIV-infected needle
  • Having HIV-infected blood, semen, or vaginal fluids get into open cuts or sores
  • Mother-to-child transmission during pregnancy, birth or breastfeeding

Many people have general flu-like symptoms from 2 to 4 weeks after an HIV infection.[4] Other symptoms, such as fever, sore throat, rash, swollen lymph nodes, night sweats, fatigue, muscle aches, chills, or mouth sores, may last from a few days to several weeks. Some people have no symptoms. The only way to know if you have HIV is to get tested.[4]

There are three stages of HIV [4]:

  • Stage 1 is acute HIV infection, where the common symptoms are flu-like. People are most contagious during this stage because of the large amount of virus in the blood.
  • Stage 2 is chronic HIV infection, also known as asymptomatic HIV infection. Though you may not have any symptoms during this stage, the virus continues to replicate in the body and can still be transmitted. People with HIV who take their medication as indicated by their healthcare provider may never progress to stage 3.
  • Stage 3 is the progression of an HIV infection to AIDS. This stage is marked by a high amount of the virus in the blood, making it easier to transmit the infection to other people. People with AIDS have a severely damaged immune system, making them highly susceptible to opportunistic diseases and serious illnesses.

Private STD consultations

What is PrEP?

Pre-exposure prophylaxis (PrEP) is the use of highly effective medication to prevent HIV infection.[5-7] PrEP for HIV prevention can reduce the risk of getting HIV from sex by about 99% and from injection drug use by at least 74%.[6] PrEP is for HIV-negative people. Therefore, you must get tested before you start therapy.[7,8]

You may benefit from PrEP if you are HIV-negative and [7,8]:

  • Have had anal or vaginal sex in the past six months with a sexual partner with HIV, and (1) have not consistently used a condom, or (2) have been diagnosed with a sexually transmitted disease (STD) in the past six months.
  • Inject drugs and have an injection partner with HIV or share needles, syringes, or other injection equipment.
  • Have been prescribed post-exposure prophylaxis (PEP) in the past and continued to engage in high-risk behavior.

You should consult with your healthcare provider if you would like to see if PrEP is an option for you.[7,8] It is also important to understand that PrEP only protects against HIV and not other STDs. You should see your healthcare provider every three months for repeat HIV testing, prescription refills, and follow-up.[7,8]

FDA-approved PrEP drugs

The FDA has approved two oral and one injection PrEP treatment options [7,8]:

  • Truvada®: A combination oral option taken once daily for people at risk for HIV through sex or injection drug use.[7,8]
  • Descovy®: A combo daily oral treatment for sexually active men and transgender women at risk of HIV infection. This medication is not for people assigned as female at birth who are at risk for HIV through receptive vaginal sex.[7,8]
  • Apretude®: A long-acting injection administered every two months for people at risk for HIV through sex who weigh at least 77 pounds.[7,8]

PrEP is only available through a prescription by a healthcare provider.[7,8]

Other ways to prevent the spread of HIV

PrEP is only one way to prevent HIV. Here are some other ways you can prevent HIV and reduce your infection and transmission risk [5]:

  • Use protection during sex. Latex condoms provide the best protection against HIV.
  • Protect yourself during sex by choosing sex with less risk. There is little to no risk of getting HIV through oral sex.
  • If you inject drugs, protect yourself by using new, clean syringes, not sharing, or choosing not to inject drugs.
  • Prevent perinatal transmission by getting tested and started on appropriate HIV therapy.
  • Take post-exposure prevention treatment, also known as PEP.
  • If you have HIV, take your medication as prescribed.

HIV testing and Everlywell

If you want to know your HIV status, you can consider an at-home HIV test through Everlywell. The at-home lab test allows you to collect the sample from the comfort and privacy of your own home and mail it to a certified lab for testing. Once your results are available, you can easily view them on Everlywell's secure online platform. Knowing your HIV status can help you protect yourself and others. To speak with a healthcare provider about HIV prevention and/or treatment, book an appointment via Everlywell's option for STD treatment online.

HIV PrEP with Apretude®: how does Apretude® work?

How effective is Truvada® in preventing HIV?

What is Descovy® used for?


  1. HIV/AIDS timeline. Centers for Disease Control and Prevention. Accessed May 16, 2023
  2. Basic statistics | HIV Basics. Centers for Disease Control and Prevention. Last Reviewed June 21, 2022. Accessed May 16, 2023.
  3. What is HIV& AIDS? Planned Parenthood. Accessed May 16, 2023.
  4. About HIV/AIDS. Centers for Disease Control and Prevention. Last Reviewed June 30, 2022. Accessed May 16, 2023.
  5. Prevention | HIV Basics. Centers for Disease Control and Prevention. Published June 1, 2021. Accessed May 16, 2023.
  6. Pre-exposure prophylaxis (PrEP). Centers for Disease Control and Prevention. Published July 5, 2022. Accessed May 16, 2023.
  7. US Public Health Service: Preexposure Prophylaxis for the Prevention of HIV Infection in the United States (2021 Update) – Clinical Practice Guideline. Centers for Disease Control and Prevention. Accessed May 17, 2023.
  8. Pre-exposure prophylaxis: Prep medication. Accessed May 16, 2023.
Everlywell makes lab testing easy and convenient with at-home collection and digital results in days. Learn More