Are you PrEP-d for your Saturday night? St.Emlyn’s


Background:I have tried to write this post using non-medical jargon and I’ve not expanded so much on the background medical evidence. I am hoping that this post will be disseminated outside of our usual circle of readers as I think PrEP is likely to become an important tool in the fight against HIV/AIDS and I believe our patients will also benefit from reading the below post.

There are ample references at the end of the post for you to browse and appraise the medical literature should you wish to do so.

What is PrEP?

As an emergency physician, you will most probably have come across PEP or PEPSE (post-exposure prophylaxis) in the context of your practice. We had briefly cover it here at StEmlyns years ago.

PrEP stands for Pre-Exposure Prophylaxis. You will have guessed and in one sentence, PrEP is a tablet you take reguarly, which protects you from HIV. This is probably going to prove to be a game changer in terms of tackling the HIV/AIDS epidemic worldwide.

The tablet active ingredients are tenofovir TDF and emtricitabine FTC. This is most commonly known under the trade name Truvada but several products are available on the market under different names. Generic PrEP which has been approved by some government health organisations is just as effective as branded PrEP and contains nothing more, and nothing less so the efficacy of the drug is exactly the same regardless of which the patient takes.

The evidence behind PrEP

As mentioned above, I am trying NOT to make this post very clinical so folks outside of our profession can also have an understanding of what PrEP is and what it not.

I will mention three studies and provide links to it if you would like to read the relevant literature and critically appraise it. At StEmlyns, we always encourage you to do so anyway and do not take anything for granted!

As this is something relatively recent with an emerging picture, I would welcome your ideas/criticism under the comments section.

If you are a clinician then you will need to have a look at these studies if you are curious enough: the first one was the iPrEX (in Spanish Iniciativa Profilaxis Pre-Exposición or “pre-exposure prophylaxis initiative” in English) study1, the French iPERGAY study2 and the UK PROUD 3(Pre-exposure Option for reducing HIV in the UK: immediate or Deferred).

Who should consider taking PrEP

PrEP is aimed at people who are HIV negative and who have unprotected sex, either because condoms are not available or they have decided for various reasons not to use condoms.

This theoretically benefits the groups that are the most exposed to HIV: the LGBT community, serodiscordant couples, sex workers, people who partake in chemsex4, LMIC countries (where condoms are not always available), anyone who decides they have unprotected sex with a high risk partner. There is an argument that the last two groups would best benefit from using condoms in terms of cost-benefit as condoms are much cheaper. If you however consider the costs associated to lifelong treatment in HIV positive patients and compared to that of PrEP, it becomes obvious that this is a much more cost-effective prevention approach.

The benefits are also psychological as people started on PrEP have reported that they suddenly started to relax and feel less anxiety having sex with high risk partners.

Most importantly, there is the large-scale benefit of tackling the HIV pandemic which affects all continents and is a large financial and health burden for every nation.

 How is it relevant to Emergency Medicine?

Regardless of if you work in a university teaching hospital based in a cosmopolitan city with a strong LGBT community or a smaller hospital far from the mad crowds, you will potentially have to advise and/or treat patients on PrEP. It is essential you understand what it is for and what sort of interactions you might encounter with other drugs/medicines.

Help is very often required out-of-hours, during the weekend and holiday periods when your local sexual health clinic will be closed.

If you are a clinician then you might want to have a look at some of our previous posts on  how to take a sexual history5 and all you ever needed to know about chemsex4.

How do you take PrEP

There are several different regimes available and the choice will be determined on the frequency of sex and how far in advance one plans sex. These plans are derived from three different studies that underpinned the efficacy of PrEP in high-risk groups.

The French and Canadian study Ipergay advocated taking PrEP “on demand” so leading to a specific event. This would suit someone for example who is going on a “special” holiday and are planning to have unprotected sex or those who have sex on say weekends only.

The UK PROUD3 study and the USA-based iPrEX study1 (which led to the US approval of PrEP) suggest daily dosing.

It is important to mention that daily PrEP is the only method that is suitable for unprotected vaginal sex.

It is unfortunately beyond the scope of this blog post to detail all the regimes so I suggest you consult this link if you want to know more about it.

How to do you get PrEP

PrEP is not available on the NHS in the United Kingdom, apart in Scotland where you can get it free of charge.

PrEP can however easily be bought online and imported into the UK, without breaking the law. It is an interesting legal loophole as the UK Customs allows anyone to import a ‘personal amount’ of pharmaceutical drugs, with a personal amount being specified as up to 3 months worth.

Some online pharmacies will ask you to have a prescription and some won’t.

This is reportedly is not a reflection on how reputable or trustworthy that company is and the UK law does not cover the selling process itself, it covers only what you’re importing into the country.

The potential drawbacks

It sounds as though real progress has been made in what is an increasingly interesting and academically fascinating area around the prevention of AIDS/HIV, but I have a couple of reservations.

First is the potential development of resistance of the HIV against the very drug we use in PEP and treatment of HIV/AIDS. I am unsure how real this risk is as I am not a microbiologist/virologist, although others have raised similar concerns if wither PrEP or HIV treatment is not adhered to7, although overall the risk is considered to be small by consensus bodies8,9. There is the concern though as we haven’t really proven this one way or the other.

Secondly, PrEP does not protect against any other STI, only HIV. You need to take other precautions in addition to PrEP to protect yourself from all other STI (such as condoms). Bearing in mind that PrEP is mostly utilised by the very population in which the use of condoms has failed, I see a real challenge looming up here. We have already seen significant problems with multi drug resistant gonoccocus which may lead to a time when STIs become untreatable6.

Finally, if you have any concerns or worries, or even if you just know that you at risk there is no substitute for regular STI/HIV testing. In Virchester our GUM colleagues are amazing and are there to support you (even if you have strict adherence to PrEP).

Play safe everyone!



@baombejp on Twitter



Grant RM, Lama JR, Anderson PL, et al. Preexposure Chemoprophylaxis for HIV Prevention in Men Who Have Sex with Men. New England Journal of Medicine. 2010;363(27):2587-2599. doi: 10.1056/nejmoa1011205
Molina J-M, Capitant C, Spire B, et al. On-Demand Preexposure Prophylaxis in Men at High Risk for HIV-1 Infection. New England Journal of Medicine. 2015;373(23):2237-2246. doi: 10.1056/nejmoa1506273
McCormack S, Dunn DT, Desai M, et al. Pre-exposure prophylaxis to prevent the acquisition of HIV-1 infection (PROUD): effectiveness results from the pilot phase of a pragmatic open-label randomised trial. The Lancet. 2016;387(10013):53-60. doi: 10.1016/s0140-6736(15)00056-2 [Source]
All you wanted to know about Chemsex but were afraid to ask. St.Emlyn’s. Published December 15, 2015. Accessed August 23, 2017.
Taking a sexual history in the ED. St.Emlyn’s. Published August 4, 2015. Accessed August 23, 2017.
Unemo M, Nicholas RA. Emergence of multidrug-resistant, extensively drug-resistant and untreatable gonorrhea. Future Microbiology. 2012;7(12):1401-1422. doi: 10.2217/fmb.12.117
Does PrEP Induce Drug Resistance? Pharmacy Times. Published August 10, 2016. Accessed August 23, 2017.
Dimitrov DT, Boily M-C, Hallett TB, et al. How Much Do We Know about Drug Resistance Due to PrEP Use? Analysis of Experts’ Opinion and Its Influence on the Projected Public Health Impact. Apetrei C, ed. PLOS ONE. 2016;11(7):e0158620. doi: 10.1371/journal.pone.0158620
van de Vijver DAMC, Nichols BE, Abbas UL, et al. Preexposure prophylaxis will have a limited impact on HIV-1 drug resistance in sub-Saharan Africa. AIDS. 2013;27(18):2943-2951. doi: 10.1097/01.aids.0000433237.63560.20

Cite this article as: Janos Baombe, "Are you PrEP-d for your Saturday night? St.Emlyn’s," in St.Emlyn's, August 23, 2017,

1 thought on “Are you PrEP-d for your Saturday night? St.Emlyn’s”

  1. Pingback: Are you PrEP-d for your Saturday night? St.Emlyn’s – Global Intensive Care

Thanks so much for following. Viva la #FOAMed

Scroll to Top