PEP, PrEP, and TasP

[T-Plus 26 Days... Almost a month!] 

26 days and 26 pills into my first prescription for PrEP. I can't believe it's been nearly a month already! Sure, it was rough at first, but it's been great for the past couple weeks now. There have been some really interesting social side-effects to getting on it that I didn't expect, though.

The first of these is that many people seem to feel a lot more entitled to ask me questions about my sex life. That isn't a problem for me, since a lot of my work involves talking about different aspects of human sexuality, but it's still surprising. A lot of those sorts of questions ultimately come down to asking me why I'm getting on PrEP: do I have an HIV-positive partner? (I don't, but I could!) Do I want to have sex bareback? (Sure, sometimes, but that's not really why I'm on PrEP.) How risky am I, exactly? (Depends on a lot of things.)

The other thing that I've found is a lot of confusion about PrEP versus other medication-based prevention methods (when people have even heard of them). There are a lot of ways to prevent HIV transmission, but there are really only three major types that use medications at the moment: PEP, PrEP, and TasP. To make these a little easier to tell apart, I made a chart, which you can take a look at below (I'll describe the three prevention methods in more detail in a moment).

PEP, PrEP, and TasP - Three Medication-Based HIV Prevention Methods.

Alright, so the one thing that all three of these prevention methods have in common is that they all involve getting a prescription for one or more HIV medications (anti-retroviral therapies/medications, or ART's). The medications work exactly the same way inside the body no matter why a person is taking them, though different medications prevent the virus' activity in lots of different ways. Each method is intended for a different stage in HIV's "life-cycle".

Please forgive me in advance, but for the sake of making these prevention methods a little easier to understand, I'm going to use the analogy of hormonal birth control. I know it's drastically over-simplifying things, and I'm not trying to compare pregnancy to illness except very, very loosely. Okay...


PEP - Post-Exposure Prophylaxis - PEP is a method of HIV prevention for emergencies; a person who believes they're HIV-negative (a doctor will confirm this before prescribing PEP) and thinks or knows that they've just been exposed to HIV can get a prescription for one or two ART meds to stop the infection from taking hold before it can get started. PEP is a short-term prescription, normally lasting for about a month. PEP is usually prescribed by an emergency room doctor (because it has to be prescribed within 72 hours of the suspected exposure), but it can be prescribed by a Primary Care Provider as well.

You can think of PEP as being like the morning-after pill for HIV: you get it right after sex (or blood contact, in the case of PEP) to stop things right after the fact.

Strict adherence to a PEP regimen is necessary to ensure it is most effective.


PrEP - Pre-Exposure Prophylaxis - PrEP is a medium- to long-term prevention strategy that involves getting a prescription for a single, daily ART pill (presently Truvada, which contains two medications - tenofovir disoproxil fumarate and emtricitabine) in order to prevent HIV infection in people that are confirmed to be HIV negative. Going on PrEP is a commitment, because as with PEP, strict adherence ensures that PrEP is most effective, but taken regularly and on time, taking PrEP can prevent HIV infection even through repeated exposures over an extended time.

People get on PrEP for a lot of reasons: yes, some because they absolutely hate condoms; but also for some because they have an HIV-positive partner (or might not want HIV to stand in the way of possible future partners); because they use IV drugs or have a lot of anonymous sex; or because they simply want to reduce their risk for contracting HIV. Most people take PrEP for some months to years during periods of higher risk for HIV infection.

You might think of PrEP as being a bit like going on the pill - it's a daily dose of a medication that, if taken properly, stops things in advance.


TasP - Treatment as Prevention - TasP refers to people who are HIV-positive, who are adherent to their HAART regimen and virally suppressed (the amount of active virus in the person is "undetectable" - so little that it's virtually missing when a doctor looks at their blood). A person who's HIV is undetectable has a much, much lower chance of transmitting their virus to a partner regardless of any other prevention methods. Yes, you read that right - an HIV-positive person whose virus is well-managed can theoretically have unprotected sex, even repeatedly, and not pass on the virus to their partner. This doesn't mean a condoms shouldn't be part of the equation, too (that goes for PrEP as well), but it means that with good medical care, safe and active sex-lives are possible for and with poz folks.

The birth control metaphor kind of falls apart here. A better analogy for TasP might be taking medication to treat herpes - it's a lifelong regimen, but while on it, the risk of transmission is reduced.

As with PEP and PrEP, strict adherence to a HAART regimen is necessary to ensure the greatest risk reduction.

I hope this post has been helpful for some people. You're more than welcome to share the image above, as long as you don't crop or edit it in any way. You can find a shareable post - including the chart - on Truvotter PrEP's Facebook page.