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Chemsex & HIV

  • Chemsex involves using one or more (specific) drugs to enhance sex.
  • Taking drugs to deliberately enhance sex is a different kind of recreational drug use, and has specific sexual health risks.
  • The three main drugs used for chemsex are GHB, mephedrone and crystal meth. Each one has very different mental and physical effects. 
  • Participating in chemsex is never 100% safe, but there are precautions you can take to stay safe and protect yourself from HIV. 
  • If you’ve had chemsex and are worried you’ve put yourself at risk of HIV, get advice from a sexual health professional or visit an accident & emergency department as soon as you can. 

Chemsex (also known as chemfun, party and play or PNP) involves using one or more drugs to enhance sex; it can last for many hours at a time, and often with multiple sexual partners.

Find out more about the risks involved in chemsex and why it increases your chances of HIV infection...Nodequeue

What is chemsex? 

Chemsex is a term that describes the sex that gay men have when using certain drugs. It can involve groups (including larger party settings), couples or lone masturbation. It’s important to remember that straight people often use drugs and alcohol for sex too, and though it may not come under the chemsex definition, there can be sexual health (and other) risks for them too. 

Taking drugs for chemsex is different to drinking alcohol or taking drugs recreationally. This is because the associated drugs, or “chems”, which are used to deliberately enhance sexual experiences also induce a different kind of sexual disinhibition among users.

Usually people do it to alter the physical sensations they have during sex (increased pleasure and ability to have sex for longer), or to change their psychological experiences (increasing their confidence or removing inhibitions).

Which drugs are used for chemsex?

There are three popular drugs used during chemsex: 

  • gammahydroxybutyrate/gammabutyrolactone (also known as GHB/GBL, G or Gina) 
  • mephedrone (meph or meow)
  • crystal methamphetamine (crystal meth)

They are sometimes taken on their own or together with alcohol or other drugs (such as cocaine or ecstasy).

What are the risks of chemsex?

Chemsex drugs are mind-altering substances, so if you mix them with sex you’re increasing your risk of HIV and sexually transmitted infections (STIs) in a number of different ways:

  • with less physical inhibitions you’re less likely to use condoms, even if you intend to beforehand
  • you may not remember what activities you’ve taken part in and whether you used condoms
  • if you’re involved in a long session, you might forget to take your pre-exposure prophylaxis (PrEP) medication, increasing your vulnerability to HIV if you’re not using condoms
  • if you’re living with HIV, you might forget to take your HIV medication, which helps to keep you undetectable and uninfectious to your partners
  • you may have sex with a number of people, who may or may not be HIV positive, increasing your chances of exposure to HIV
  • you may have more forceful sex than you’re used to, because of the anaesthetic effects of drugs like GHB. The thin lining of the anus can be easily damaged or torn through forceful, unlubricated anal sex, increasing the risk of HIV infection and other STIs, including hepatitis C
  • you can 'lose time' as a result of long lasting sex sessions – this may affect your chances of preventing HIV transmission with emergency post-exposure prophylaxis treatment (PEP), which needs to be taken within 72 hours of infection to be effective
  • if you inject mephedrone or crystal meth with shared needles (otherwise known as slamming), you’re increasing your risk of both HIV and hepatitis C infection

The potency of drugs like GHB also affects your wider health and safety. GHB increases your chances of ‘passing out’, leaving you more vulnerable to sexual assault. Whatever the circumstances, and whatever drugs you may have taken prior to sexual activity, remember that sexual assault is never acceptable and is never your fault. 

The combination of chems and lack of sleep can also create a short-lived psychosis, during which people can feel paranoid, frightened, or believe they are being persecuted by others. These episodes can sometimes involve very convincing beliefs or hallucinations.

Lethargy or crashing is also common after a drug session (also known as a comedown), as well as psychological dependence or, with the overconsumption of substances, an overdose which can be fatal.

Chemsex safer ways to play

How can I reduce the risks of chemsex?

It’s important to never feel pressured into taking any substances that you aren’t comfortable or familiar with. However, while having sex on drugs can never be 100% safe, chemsex is a way for some people to enjoy or explore their sexuality. 

If you’re planning on participating in chemsex, it’s always good to think about ways to take responsibility for your own safety and sexual health, as well as that of those partying with you.

  • Pack some protection – make sure you have lots of condoms and lube to hand! Pre-exposure prophylaxis (PrEP) may also be an option to protect you from HIV. 
  • Know your status - Most HIV transmissions occur among people who have only recently caught HIV and don't know yet that they are positive. Regular testing to check your status will help to keep yourself and others healthy.
  • Party with people you trust – plan to keep an eye on each other and put rules in place for group safety
  • Set your limits - talk about preferred methods of protection and be clear about what kinds of sex you are and aren't into
  • Stay aware – keep tabs of what drugs and dosage you’ve consumed, and how they might affect your overall wellbeing
  • Set reminders - if you’re taking PrEP to prevent HIV, or require antiretroviral medication (ARVs) if you are living with HIV, use an alarm to ensure you take your pills at the correct times.

What support is available?

There are many specialist drugs and alcohol counselling services that you can get in touch with for non-judgemental support, advice and information about drugs and sex. Many sexual health clinics also have staff that are familiar with chemsex and can offer support.

If you’ve had chemsex and are worried that you may have put yourself at risk of HIV you should speak to a sexual health professional as soon as possible for advice or visit an accident and emergency department as soon as possible for advice.

You will probably be offered PEP as a form of emergency treatment if you’ve contacted them within 72 hours of suspected HIV exposure. At a clinic you will also be offered screening tests for sexually transmitted infections (STIs), including HIV.  

Your healthcare provider will also be able to provide help if you are concerned about addiction or other effects that chemsex drugs are having on your physical or mental wellbeing. 

If you’re finding it difficult to locate a healthcare advisor in your area who can give you the appropriate chemsex support, check out this interactive online tool in multiple languages, for more advice on how to stay safe and make manageable lifestyle changes. 

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Last full review: 
25 August 2017
Next full review: 
24 August 2020
Last updated:
01 October 2019
Last full review:
25 August 2017
Next full review:
24 August 2020