What is pre-exposure prophylaxis (PrEP)?

If you’re at risk of contracting human immunodeficiency virus (HIV), PrEP can help. Prophylaxis is a therapy that prevents disease. PrEP uses medications to lower the risk of HIV.

You may be at risk for HIV if you:

  • Have anal or vaginal sex with a person infected with HIV or doesn’t know their HIV status.
  • Share needles with someone who is HIV-positive or doesn’t know their HIV status.

What is human immunodeficiency virus (HIV)?

HIV is an infection caused by a virus that attacks your body’s immune system. People transmit the virus through:

  • Having unprotected sex with someone who has HIV.
  • Sharing needles contaminated with the virus.

Severe cases of HIV can lead to acquired immune deficiency syndrome (AIDS). This condition weakens your ability to fight infection and does not have a good outlook. This is why HIV prevention through PrEP is so important. PrEP could potentially save your life.

Who is PrEP for?

This treatment is for:

  • Adolescents and adults who don’t have HIV but may be at risk for it.
  • Women and people assigned female at birth (AFAB) at risk for HIV who are considering getting pregnant. PrEP may protect the baby from the virus during pregnancy and breastfeeding.

What happens before starting PrEP?

You'll need a prescription from a healthcare provider. Before writing the prescription, the healthcare provider will perform a physical exam and run a few tests. These tests rule out conditions that prevent you from being on PrEP, such as:

  • AIDS.
  • HIV.
  • Severe kidney impairment.

The healthcare provider will also test you for other infections that can occur in people at risk for HIV, including:

What are the types of PrEP?

There are a few options, including:

  • Truvada®, daily PrEP in pill form you take by mouth. It includes two medications that block enzymes preventing the virus from spreading to other tissue. This option is for everyone, regardless of gender or sex assigned at birth.
  • Descovy®, also a daily pill that prevents the virus from reproducing. This option consists of a different set of medications. Descovy is approved only for people assigned male at birth (AMAB), including cisgender men, transgender women and nonbinary people who are AMAB.
  • Apretude®, long-acting injectable PrEP. Care starts with two injections, one month apart. You then receive Apretude injections every two months. This option is for everyone, regardless of gender or sex assigned at birth.

What are the side effects of PrEP?

Side effects depend on the type of PrEP you receive.

Daily oral PrEP

Common side effects include:

Rare but serious side effects may include:

  • Bone loss.
  • Kidney issues.
  • Lactic acidosis, buildup of lactic acid in your blood.
  • Liver problems.
  • Rash.

Injectable PrEP

Injectable PrEP has many of the same side effects as the daily oral versions. Additional side effects include skin irritations at the injection site, such as:

  • Hardened lump.
  • Loss of sensation.
  • Swelling.
  • Tenderness.
  • Warmth.

What are the benefits of PrEP?

Taking PrEP significantly lowers your risk of getting HIV, even if you’re exposed to the virus through unprotected sex or shared needles.

How effective is PrEP?

When taken as prescribed, PrEP reduces the risk of HIV by approximately:

  • 99% due to exposure from sexual activity.
  • 74% due to exposure from shared needles.

What are the risks of PrEP?

If PrEP doesn’t work, you could develop an HIV infection. Once you have the virus, it stays with you for life.

What else should I know before deciding whether PrEP is right for me?

Additional information you should know:

  • PrEP doesn’t protect you against other sexually transmitted infections (STIs). This is why it’s essential to use condoms.
  • If you’re living with certain STIs, like hepatitis B infection, taking PrEP can worsen symptoms.

Are there drug interactions I should worry about?

The medications in PrEP may interact with other medications, including:

Do I need to take any special precautions while I’m on PrEP?

Following these guidelines can optimize results and protect you against complications:

  • Continue seeing your healthcare provider for HIV testing and other follow-up care every three months.
  • Contact a healthcare provider immediately if you think you’ve been exposed to HIV. This may include going to urgent care or the emergency room.
  • Don’t miss any doses. Doing so will make PrEP less effective.
  • Contact your healthcare provider if you think you’re pregnant or could become pregnant.
  • Practice safer sex by using a condom every time.

Will I need to be on PrEP for life?

You may wish to stay on PrEP if you continue to be at risk for HIV due to unprotected sex or shared needles.

Sometimes it’s appropriate to stop taking PrEP. Talk to a healthcare provider before discontinuing PrEP.

Reasons to discontinue PrEP include:

  • Life changes, such as quitting drugs.
  • Not being able to follow care instructions, like taking daily pills or getting tested for HIV.
  • Side effects that are disrupting your daily life.
  • You are at risk for or experiencing severe side effects.

When should I contact my healthcare provider?

While taking PrEP, contact your healthcare provider if you have:

  • Signs of severe side effects.
  • Mild side effects that don’t improve over time.
  • Symptoms of liver disease, yellowing skin or eyes (jaundice), dark-colored urine or light-colored stool.
  • Sudden mood changes, such as depression, anxiety or thoughts of suicide.

In addition, call your healthcare provider if you think you’re pregnant or could become pregnant.

A note from Cleveland Clinic

PrEP includes medications that lower your risk of getting HIV from unprotected sex or shared needles. Talk to your healthcare provider to find out if PrEP is right for you. Even if you don’t regularly see a provider, there are medical professionals in your community who can help you access this treatment. If you need help finding a provider, talk to a pharmacist or local health resource center.

Last reviewed by a Cleveland Clinic medical professional on 08/01/2022.

References

  • Centers for Disease Control and Prevention. Pre-Exposure Prophylaxis (PrEP). (https://www.cdc.gov/hiv/risk/prep/index.html) Accessed 8/1/2022.
  • HIV.gov. Pre-Exposure Prophylaxis. (https://www.hiv.gov/hiv-basics/hiv-prevention/using-hiv-medication-to-reduce-risk/pre-exposure-prophylaxis) Accessed 8/1/2022.
  • FamilyDoctor.org (American Academy of Family Physicians). Pre-Exposure Prophylaxis (PrEP). (https://familydoctor.org/pre-exposure-prophylaxis-prep/) Accessed 8/1/2022.
  • PrEP Daily from The Health Foundation of Greater Indianapolis. What Is the Difference Between Truvada vs. Descovy? (https://prepdaily.org/what-is-the-difference-between-truvada-vs-descovy/) Accessed 8/1/2022.
  • PrEP Daily from The Health Foundation of Greater Indianapolis. Apretude. (https://prepdaily.org/?s=apretude) Accessed 8/1/2022.

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