What’s the Difference? PrEP vs. PEP for HIV Prevention Explained

What’s the Difference? PrEP vs. PEP for HIV Prevention Explained

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By Steve Page

Introduction – The Difference Between PrEP and PEP for HIV Prevention

Pre-Exposure Prophylaxis (PrEP) and Post-Exposure Prophylaxis (PEP) are two important strategies for preventing HIV infection. PrEP is a daily medication taken by people without HIV that can reduce the chance of contracting HIV if exposed to it, while PEP is a short course of antiretroviral medications taken within 72 hours of exposure that can stop HIV from becoming established in the body. Both strategies have been proven effective in reducing HIV transmission but there are important differences to consider when deciding which is best for you.

What is PrEP?

PrEP is an acronym for Pre-Exposure Prophylaxis, which is a daily medication taken by people who do not have HIV to reduce the risk of becoming infected with the virus. PrEP works by blocking the virus from taking hold in the body if one is exposed to it. PrEP is most effective when taken regularly and consistently, and it has been demonstrated to reduce the risk of HIV infection by up to 99% when used correctly. PrEP should be considered by anyone who is at a high risk of HIV exposure, such as men who have sex with men or people in relationships with HIV-positive partners.

Side Effects of PrEP

Although serious side effects of PrEP are rare, they can occur. The most common side effects include nausea, diarrhea, fatigue, and headache. These side effects usually disappear over time, but if they become severe or persistent, it is important to talk to a doctor. Additionally, PrEP can interact with some medications, so it is important to inform your doctor about all other medications that you are taking before starting PrEP.

Where to Find PrEP

PrEP is available by prescription from doctors or through online telemedicine services. It is important to obtain PrEP from a trusted source to ensure that you are receiving genuine medication that is safe and effective. When obtaining PrEP online, it is important to make sure that the website is legitimate and that the medications are sourced from a licensed pharmacy.

What is PrEP?

PrEP stands for Pre-Exposure Prophylaxis, and is a medication taken by individuals who are at risk of HIV infection in order to reduce their chances of acquiring the virus. PrEP works by blocking a virus’ ability to infect an individual’s cells. This prevents the virus from entering the body and spreading, thus reducing the risk of HIV transmission.

PrEP is taken as a pill, usually once a day, and must be taken consistently in order to be effective. It should be taken about two hours before sexual contact for maximum effectiveness. PrEP is not a form of contraception and does not protect against other sexually transmitted infections (STIs).

When taken consistently and correctly, PrEP is highly effective in preventing HIV infection. Studies have shown that PrEP can be up to 99% effective at preventing HIV, so long as it is taken as directed. However, PrEP does not provide immediate protection, so it is important to discuss timing with your healthcare provider.

It is recommended that individuals who are at risk of contracting HIV should consider PrEP if they do not use condoms consistently and if their partners are known to have HIV. PrEP is also recommended for individuals who have multiple sexual partners, or who engage in activities that increase their risk of HIV infection, such as sharing needles.

Those who are interested in taking PrEP should speak with a healthcare provider to discuss their risks, the potential side effects of taking PrEP, and any questions they may have.

Side Effects of PrEP

PrEP (or pre-exposure prophylaxis) is a medication taken to help prevent HIV infection. It works by reducing the amount of HIV in the blood, making it much harder for the virus to take hold and cause an infection.

However, like all medications, PrEP does come with the potential of side effects. It’s important to understand the likelihood of experiencing side effects, so you can make a better informed decision about whether PrEP is the right choice for your HIV prevention.

The most common side effects associated with PrEP are nausea and headache. These side effects are usually mild and short-lived, and can be managed or alleviated with simple steps. You may also experience stomach pains and joint pain, which should resolve within a few days.

Less common but more serious side effects include kidney problems, liver problems, allergic reactions, and depression. If you experience any of these more severe side effects, you should consult with your medical professional immediately.

To reduce the severity of side effects associated with PrEP, it’s important to follow your doctor’s instructions when taking the medication. Take PrEP exactly as prescribed, and avoid taking too much or too little of the medication. It’s also important to drink plenty of fluids while taking PrEP, to help reduce the risk of dehydration and kidney problems.

Ultimately, PrEP is a very safe and effective way to prevent HIV infection. While there are side effects associated with PrEP, they do not outweigh its overall effectiveness. If you’re considering PrEP as a means to prevent HIV, talk to your doctor for further advice.

Where to Find PrEP

When it comes to HIV-prevention, PrEP is an essential tool. However, it’s important to get your PrEP from a trusted source so that you can be sure it’s safe and effective. Here are some options for obtaining PrEP:

  • Visit your local doctor or clinic. Most doctors and clinics are able to prescribe PrEP, and many offer discounted rates or other assistance programs so that PrEP is affordable and accessible. You may also be able to find free PrEP programs in your area.

  • Order PrEP online. While it’s generally recommended that you visit your doctor to discuss the use of PrEP, some websites allow you to order and receive PrEP without a prescription. It’s important to use caution when ordering PrEP online and ensure that the product you’re receiving is legitimate and safe.

  • Purchase PrEP at a pharmacy. Some pharmacies now offer PrEP, though it may not be available everywhere. Ask your local pharmacy if they carry PrEP and what options they have for purchasing it.

It’s important to remember that PrEP must be taken consistently and correctly in order to be effective. Talk to your doctor or healthcare provider about how to take PrEP correctly and about any other questions or concerns you have. With the right information, you can make an informed decision about whether PrEP is right for you.

What is PEP?

PEP, or post-exposure prophylaxis, is a treatment plan that you can use after being exposed to the HIV virus. The goal of PEP is to prevent HIV infection from taking place by using a combination of two or three antiretroviral medicines together for a month. PEP must be started within 72 hours of exposure, and it is more effective the earlier it is taken.

PEP works best when used correctly. It is not 100% successful in preventing HIV infection, but studies have shown it to be up to 80-90% effective if used correctly and consistently. Common side effects associated with PEP include nausea, vomiting, headaches, and fatigue. In rare cases, PEP may cause an allergic reaction or other more serious side effects. It is important to talk to your doctor about any side effects that you experience.

PEP is only meant to be used in emergency situations and should not replace other methods of preventing HIV infection, such as the consistent use of condoms. PEP should also not be used as a regular method of contraception or as a way to reduce the risk of other sexually transmitted infections.

Side Effects of PEP

The medications used in post-exposure prophylaxis (PEP) can cause both mild and severe side effects. Starting the PEP treatment within 72 hours after a potential HIV exposure increases its chances of success in helping to prevent HIV infection, but it can still be taken up to 4 weeks after potential exposure.

Common side effects associated with PEP include nausea, vomiting, diarrhoea, headaches, fatigue, rash and fever. The most common side effect is nausea which can be eased by taking the medications with food. Taking an antiemetic like ondansetron can also help to reduce nausea.

Some more severe side effects associated with PEP include liver toxicity, kidney damage and skin discolouration. These are rarer but can occur. If you have any of these symptoms, you should contact your doctor or HIV clinician immediately.

Your doctor may ask you to have regular blood tests to check for potential side effects of the medications and to monitor your health. If you have any concerns about potential side effects, it is important to discuss them with your doctor or HIV clinician.

Taking preventive measures like eating regularly before taking the drugs, drinking plenty of water and avoiding alcohol can help to reduce the severity of the symptoms associated with PEP.

Where to Find PEP

It is important to obtain Post-Exposure Prophylaxis (PEP) from a trusted source. PEP can be used to prevent HIV transmission after known or possible exposure to the virus, and it is essential that only trusted medications are used. There are three primary sources of PEP: medical providers, pharmacies, and community organizations.

Medical Providers

The first and most common source of PEP is through a medical provider. Medical providers are health care professionals such as physicians and nurse practitioners who can provide a prescription for PEP. If you think you have been exposed to HIV, you should contact a medical provider right away. They will assess your risk and provide the medication if appropriate.


Another option for finding PEP is to visit a pharmacy. Most pharmacies are stocked with antiretroviral medications and can provide the necessary pills for PEP. However, it is important to note that there are specific procedures that must be followed. It is not recommended that you try to purchase PEP from a pharmacy without a prescription from a medical provider.

Community Organizations

Finally, there are a number of community organizations that provide access to PEP. These organizations may be able to provide the medication at no cost or at a discounted rate. Additionally, they may offer support with getting an appointment with a medical provider and other services related to HIV prevention. Finding a local organization can be done through a simple internet search or by asking your doctor.

In conclusion, there are several options for obtaining PEP. The most reliable method is to visit a medical provider, but pharmacies and community organizations can also provide access to the medication. It is important to obtain PEP from a trusted source and to follow the instructions provided.

Why Choose Between PrEP and PEP?

When it comes to HIV prevention, there are two key medications to consider: PrEP (pre-exposure prophylaxis) and PEP (post-exposure prophylaxis). Both have their own unique benefits and drawbacks, so it is important to weigh up all your options before deciding which one is right for you.

PrEP is taken daily as a preventative measure and is highly effective in stopping the transmission of HIV. It works by blocking the virus from taking hold in your body if you’re exposed to it. PrEP is also relatively inexpensive, making it an accessible option—especially in comparison to PEP.

PEP, on the other hand, is taken after potential exposure to the virus and should be started within 72 hours of that first exposure in order to be effective. It involves a course of three antiretroviral medications over a period of 28 days and can be costlier than PrEP.

To decide between PrEP and PEP it is important to consider factors such as cost, effectiveness, and lifestyle. If you have unpredictable or high-risk exposures to HIV, it might make more sense to take PrEP on an ongoing basis, whereas PEP should be taken in the event of a known potential exposure.

It is important to speak to a doctor or healthcare professional to get their opinion on the best course of action for your individual circumstances. They will be able to provide detailed advice on the advantages and disadvantages of each option, so you can make an informed decision that best fits your needs.


PrEP and PEP are both effective methods for preventing HIV infection, but may not be suitable for everyone. PrEP is a medication taken before potential exposure to HIV, while PEP is taken after potential exposure.

PrEP can be taken daily or ahead of times when you may be exposed to HIV risk, and has proven to be very effective in reducing the risk of HIV infection. It can be obtained with a doctor’s prescription and is generally well-tolerated.

PEP is taken within 72 hours of potential HIV exposure, and while it is less effective than PrEP at preventing HIV infection, it can offer some protection. It is significantly more expensive, however, and may have more side effects than PrEP.

Ultimately, it is up to each individual to decide what is best for them given their lifestyle, available resources, and risk profile. Both PrEP and PEP can be an effective tool for reducing the risk of HIV infection, so long as they are used safely and effectively.

Frequently Asked Questions

  • Q: What are PrEP and PEP?
    A: PrEP (Pre-exposure Prophylaxis) and PEP (Post-exposure Prophylaxis) are medications used to reduce the chance of HIV infection. PrEP is taken before possible HIV exposure in order to reduce the chance of HIV transmission, while PEP is taken after a possible exposure to HIV to reduce the risk of infection.
  • Q: How do PrEP & PEP work?
    A: PrEP and PEP work by providing a daily dose of antiretroviral medication which blocks the transmission of HIV when taken correctly. PrEP works by preventing HIV from taking hold in the body and multiplying if exposure to the virus occurs, while PEP is taken after exposure to the virus in order to stop it from replicating.
  • Q: Are PrEP & PEP effective?
    A: When taken properly, PrEP and PEP can be up to 99% effective in preventing HIV infection. PrEP has been found to be particularly effective among gay and bisexual men and transgender women who are at high risk for HIV.
  • Q: What are the side effects of PrEP and PEP?
    A: PrEP and PEP typically do not have major side effects, though there can be some minor side effects such as headaches, nausea, vomiting, diarrhea, and weight gain. The most common side effects of PrEP are headaches. Additionally, PEP can lead to fatigue, increased anxiety, and sleep disturbances.
  • Q: Where can I access PrEP and PEP?
    A: PrEP and PEP are available through specialized HIV health care providers or HIV organization, as well as online pharmacies. These medications can also be accessed through some insurance plans or government programs, such as the Ryan White HIV/AIDS Program.
  • Q: Why should I choose between PrEP and PEP?
    A: PrEP is generally considered the more cost-effective option, as it can be taken daily to prevent HIV infection. PEP is only taken after potential HIV exposure, and as such it cannot be relied upon as a regular form of HIV prevention. Thus, it is important to assess your risk of HIV infection, and the likely cost and effectiveness of each option before deciding which to choose.
  • Q: What are the benefits & drawbacks of using PrEP and PEP for preventing HIV?
    A: PrEP and PEP provide an effective way to protect against HIV infection when taken correctly and as prescribed. PrEP and PEP can be accessed through prescription and insurance plans, and are relatively affordable. The main drawback of PrEP and PEP is that they must be taken regularly in order to be effective, and the side effects can range from mild to moderate.