What is PEP?
Post-Exposure Prophylaxis (PEP) is a drug therapy to reduce (but not eliminate) the chance of HIV infection after possible exposure. PEP is for situations where there is a high risk of transmission. Research has shown that there may be a window of opportunity to prevent HIV transmission in the first few hours or days after being exposed to HIV. During this time, medications may be able to prevent HIV infection in people who did not have HIV prior to the exposure. PEP is not a cure. The most effective ways to prevent HIV infection are safer sex and safer injecting practices. PEP is not a treatment to be taken regularly because of the short-term and unknown long-term side effects of the medication.
Like any virus, HIV works by infecting certain cells and then producing more virus in those cells. It takes a few days for this process to happen and the goal of PEP is to prevent the reproduction of virus in those first cells. These infected cells then die naturally in the body without new copies of HIV being produced to infect other cells.
PEP is available to people who have or may have been exposed to HIV. This may include:
• Sexual exposure
• Exposure through injecting drug use or sharing injecting equipment
• Injuries, e.g. trauma, physical or sexual assault
• Needlesticks and other exposures that occur while providing care to an HIV infected person.
The 'source individual' needs to be known to be HIV positive, strongly suspected of being HIV positive, or be in a high-risk group for HIV. An assessment by a health care professional is required to determine the likely level of risk of exposure to HIV and then a shared decision will be made by the person possibly exposed and the provider to decide if PEP is appropriate.
PEP may be able to stop exposure to HIV from leading to infection, but you must act fast. To be most effective, it should be started within 72 hours of the exposure. The earlier PEP is started, the more effective it may be. If you seek PEP more than 72 hours after exposure, it is much less likely to be effective.
Currently, there are no scientific studies proving that PEP is effective for people experiencing risks due to exposures in the non-occupational settings. Non-occupational post-exposure prophylaxis (NPEP) is the use of PEP outside the work setting, usually from sexual exposure or injection drug use. However, there is evidence from the occupational setting and evidence which is based on a number of animal studies and some studies of different at-risk populations. PEP has been shown to decrease the risk of HIV transmission by 81% in healthcare workers who received PEP after being exposed to HIV in the workplace. Studies of animals infected with HIV show that giving PEP reduces the risk of HIV transmission. In addition, mother-child transmission can be reduced by 69% with the use of pre-natal PEP combined with 6 weeks PEP therapy for the infant.
PEP is the use of medications to prevent initial infection and replication of HIV in the body and to allow the immune system to eliminate the virus. The drugs are the same as those used to treat HIV. Different drug combinations are available for PEP, depending on the type of exposure and whether the source person is known to be HIV positive. There are a number of things to take into consideration when deciding which drugs will be most effective. Your doctor will discuss these with you.
PEP is not a simple drug treatment and needs to be taken for 28 days.
To be most effective, PEP drugs need to be taken on time without missing doses. You should follow up with a doctor during and after PEP therapy.
There are a number of risks relating to PEP. We recommend you discuss these with your doctor. Taking PEP will not guarantee that you will not be infected with HIV, though research indicates that in occupational exposure cases, it reduces the risk of transmission. If PEP is not successful in preventing HIV transmission and a person becomes HIV positive, there is a theoretical risk that the person may develop HIV that is resistant to the drugs used for PEP. In the short term, the drugs used for PEP can cause a number of side effects such as rash, nausea, vomiting, diarrhea, kidney stones, hepatitis and bone marrow depression. Occasionally, these side effects can be very severe. In the long term, it is unknown whether PEP can damage the immune system or the reproductive system.
Definitely. PEP is not guaranteed to prevent HIV infection. You should be tested for HIV at the time you start PEP and at one, three and six months afterwards.
PEP drugs can affect the way other drugs (prescription or non-prescription) work in the body. They also affect the way the liver processes other drugs. This can lead to an increase in blood levels of some drugs to a point that is dangerous or even lethal. It is very important to discuss with your doctor any drugs (including alcohol and other recreational drugs) you are taking or planning to take while on PEP.
No! PEP is not a vaccine or a cure for HIV/AIDS. Except for occupational exposure, it is not yet proven that PEP works and therefore, it is a "last resort" treatment. While on PEP, don't risk further HIV exposure to yourself or others by having unsafe sex or sharing needles. There is no evidence that PEP will protect against another exposure to HIV while you are taking the treatment.
PEP is available through some physicians and emergency rooms.
For an emergency room near you offering PEP, call the Louisiana Statewide AIDS/STD Infoline at 1(800) 9-AIDS-9, 1(800) 992-4379 from 10:00 am to 6:00 pm, Monday to Friday. For questions outside our hours of operation, you can contact the National Clinician's Post-Exposure Hotline at 1(888)448-4911, 24 hours a day, 7 days a week. Calls are toll-free in the US.