GHB (gamma hydroxybutyrate), sometimes referred to as GBL (gamma butyrolactone), is a sedative drug and a form of industrial solvent.

GHB (gamma hydroxybutyrate), sometimes referred to as GBL (gamma-butyrolactone), is a sedative drug and a form of industrial solvent. It is often referred to as G or Gina and is commonly used in Chemsex.

GBL comes as a clear liquid which has a chemical taste and smell. GHB, however, is either a salty liquid or a powder that is added to liquid, such as a soft drink (never alcohol).

Inside the body GBL becomes GHB.


After taking G the high can last for about two hours, increasing the desire for sex and reducing inhibitions. Some think that the effects are similar to alcohol. Other effects of G include euphoria, relaxation and tiredness.

Taking It

Most take G orally in a liquid form, usually added to some form of drink, but never alcohol.

When taking G it is important that you know what you are doing. It is very easy to overdose with G. The difference between a dose that gets you high and one that makes you overdose, causing you to 'drop' or go under (lose consciousness), is very small. It is important that you measure the amount of G you are taking. This can be done with a pipette or syringe, or in a premeasured vial. The amount it takes to overdose is so small that most consume between 0.5 and 1.5mls. However, it is difficult to know what is safe as you only need a small amount to overdose and go under. 

G can take time for you to get high; from 10 minutes to an hour. This depends on the amount you have taken, your body size, if you have eaten recently or have taken other drugs. You should never take another dose of G within two hours. This is referred to as the ‘2-hour rule’. Some guys use the clock on their phone, or a stopwatch, to keep in control of their dose timing. Writing down the dose you took, and the time that you took it, on a piece of paper or in your phone notes can also help to prevent overdosing.

Sex on GHB

GHB is one of the most common drugs used in Chemsex. This is because G can:

  • Make you feel ‘super horny’ and sexually charged (extreme arousal).
  • Make sex, like fucking or fisting, easier (relaxing the bottom).
  • Lower inhibitions, meaning you may do something that you would not do sober.
  • Make it harder to cum, meaning you can keep going for hours, or in some cases days, but also make you become focused on having sex until you cum.
  • Reduce your ability to consent. You may not be aware of what is happening to you, making it impossible to consent to anything and leaving you at risk of sexual assault and harm.

Some of the adverse side effects from G can include (but are not limited to) dizziness, vomiting, weakness, confusion, drowsiness, loss of consciousness and in some cases, even death. For many years, it was claimed that people could not become dependent on G. It has now been shown however that people who are regularly using the drug can develop a dependence on it and, can experience withdrawal symptoms such as confusion, shaking, epileptic seizure and coma.

Overdosing on G is easily done and can be fatal. The dose needs to be precise. If overdosing happens, often because a guy doesn’t feel the 'high' and takes more within two hours, it is possible to build up a tolerance to it.

Other things to note about G are: 

  • GHB is currently a class C drug. It is illegal to supply or possess it. The maximum penalty for possession is 2 years in prison plus a fine. For supplying GHB, 14 years in prison plus a fine. Furthermore, under the Sexual Offences Act 2003, it is an offence to administer G with the intent of having sex with someone without their consent.
  • You can become dependent on G:
    • Coming off G should be under the supervision of someone who has appropriate clinical competence, such as your local drug service or doctor.
    • Completely coming off G (cold turkey) can be fatal.
    • Mixing G with alcohol can be deadly. Wait several hours after drinking alcohol before using G.
  • Other drugs, like depressants (downers), alcohol, tranquilisers, ketamine, or antihistamines should not be mixed with G. These drugs can cause respiratory distress and can cause you to 'drop', ‘go under’, or unconscious, resulting in fits, coma, or death.
  • Because G can easily make you ‘go under’, there is a risk of sexual assault, or rape if you or your partner(s) cannot consent to the sex that is happening.
G and your Mental Health

Like any drug (including alcohol), G can affect your mental health and how you feel about yourself. This can also include short term memory loss, confusion or disorientation.

If you are worried about your mental health and wellbeing, you can check out our mental health section.

If you are planning to harm yourself, or have thought about suicide, then you should seek medical attention straight away. Click here for more information about getting help. 

G and HIV medication

If you are living with HIV, be aware that G can interact with the medication you are taking. This is also the case for guys who are taking PrEP.

Combining G with HIV medication (or PrEP) can result in high levels of GHB being stored in your body and result in serious side effects including a possibility of ‘going under'.

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