PEP (post-exposure prophylaxis) means taking HIV medications or antiretroviral medicines (ARV) after being potentially exposed to HIV to prevent becoming infected. The word “prophylaxis” means to prevent or protect from an infection or disease.
PEP should be used only in situations where possible exposure to HIV has occurred within the last 72 hours. PEP is effective, but not 100 percent, so you should continue to use condoms with sex partners even while taking PEP. These strategies can protect you from being exposed to HIV again and reduce the chances of transmitting HIV to others if you become infected while you’re on PEP. Based on all the data since 1995, no one has seroconverted or become infected with HIV if PEP was started within 72 hours. PEP must be taken for 30 days.
PEP is indicated depending on the type of exposure. If you have receptive anal intercourse without a condom (bottoming and barebacking) or you are the insertive partner (topping and barebacking) with an individual of unknown HIV status or HIV positive and detectable viral load, then PEP is indicated. PEP is indicated for insertive and receptive vaginal sex with an individual of unknown HIV status or HIV positive and detectable viral load. PEP is not indicated if the partner has an undetectable viral load. PEP is not indicated for oral sex involving the vagina, penis or anus. PEP is also not indicated for semen and vaginal secretion splashes on to skin. PEP is not indicated for human bites.
It’s important to know that medication components of PEP are not the same as PrEP (pre-exposure prophylaxis). If you are taking PrEP and have been taking PrEP for at least seven days and you have missed no doses, then PEP is not needed if you have possibly been exposed to HIV. PEP is only for individuals who may have been exposed to HIV and have not been on PrEP for at least seven days. PEP should not be used every time you have unprotected sex or if you are frequently exposed to HIV. The right choice in this case would be PrEP.
There are occasionally side effects from PEP and the most common are nausea and diarrhea which can be effectively managed during PEP. The side effects are not life threatening. PEP should be available at any medical provider office including urgent care clinics, emergency departments, and health departments. If you seek PEP and a clinic declines, please seek care elsewhere immediately and do not take “no” for an answer. The medications for PEP may vary depending on whether the source of HIV is known or unknown and if the source is HIV positive. If the source is HIV positive then what they are taking, and whether they are undetectable, will guide medical decision making. In general, the regimens recommended are Descovy or Truvada plus one medication from the integrase inhibitor class such as Isentress, Tivicay or the newer combo Biktarvy which can suffice for all three recommended medications.
It is important to note that the guidelines do vary for women of childbearing potential in that Tivicay should not be used due to possible birth defects. In addition to testing for HIV, tests will also be ordered to monitor kidney and liver functions and will be repeated at one month when PEP is stopped. Hepatitis B testing will also occur unless you have been vaccinated for hepatitis B.
Women of childbearing potential will also be tested for pregnancy. After the 30 days of PEP, an additional HIV test is recommended at day 30 and three months later. If there have been no further possible HIV exposures, then no further HIV testing is indicated.
It is important to remember that if an HIV positive patient is undetectable, then the patient can not pass HIV to an intimate partner. Undetectable equals untransmittable.
Wes Thompson, MHS, PA-C, AAHIVS, DFAAPA, is the medical director for Amity Medical Group.