GBL and GHB are also known as G or Gina.

GBL (gamma butyrolactone) and GHB (gamma hydroxybutyrate) are chems used during sex, often in chillouts, sex parties or when clubbing. They’re depressant drugs (‘downers’), which means they have a sedative and euphoric effect, similar to being drunk.

Both types of G can be used legitimately as industrial solvent and paint stripper-type chemicals. In most cases GBL is in the market as it’s much cheaper and easier to buy than GHB.

How it’s used

GBL is the most common form of G now and is a clear liquid that has a strong chemical smell and taste.

GHB is a clear, salty liquid with no smell. Sometimes it comes as a powder that’s added to a drink. Both are usually mixed with a soft drink, but never alcohol.

Because GBL turns into GHB inside the body, the effects of GBL can be stronger or more unpredictable.

The strength of G varies a lot so it’s hard to know what a safe dose is.

Highs and lows of G

With G, the high comes after about 20 minutes, lasting about one hour. But it may last up to four hours.

A dose of G can make users feel chilled out, horny or mildly high. It’s often used with other chems like mephedrone or crystal meth.

Too much G leaves users dizzy, confused, drowsy or vomiting – which could cause death from choking if G has knocked them out. The worst case scenarios with G are seizures, coma and death. G usage is thought to be linked to a number of deaths which have taken place in saunas in recent years.

Overdoses tend to happen when:

  • People take a second dose before the first kicks in – always give it two hours before second dosing.
  • The G is stronger than expected.
  • They’ve been drinking alcohol.


The strength of G varies a lot, so it’s hard to know what a safe dose is. A little ‘Gina’ goes a long way, with a typical dose varying from 0.5ml to 1.5ml.

There’s not much difference (less then a millilitre) between the dose that gets people high and one that has them hitting the floor. Overdosing is easy to do and comes on with little warning.

Doses need to be precise, so they’re often measured with a syringe with the needle removed. An additional danger comes when someone takes a dose and thinks nothing’s happening, so they take more.

Waiting at least two hours before taking a second dose makes overdosing less likely. Taking another shot of G within an hour makes overdosing likely as the body hasn’t processed the first shot yet.

G should never be used at the same time as alcohol as this is likely to be life-threatening. G and alcohol affect the same mechanism in the body and therefore the effect of G is increased greatly leading to overdose levels being present in the blood. If someone has already drunk some alcohol it’s advised that they wait at least two hours before taking any G and then it should only be a small amount.

Sex on G

The drug has a reputation for making people horny. Its relaxing effect can be used to help take things up the arse.

Less welcome is that it can make it harder to come or can lower peoples inhibitions, making unsafe sex more likely – and with it passing on infections such as HIV, syphilis or Hep C. If someone is a bit out of it – or totally dead to the world – it’ll be hard to control what’s happening or even remember what had happened when (or if) they come round. Guys have reported being sexually assaulted or raped while unconscious on G.

A long term relationship?

Regular users often build up a tolerance to G, needing more to get the same buzz.

It’s possible to become physically dependent on G with regular usage. The best way to avoid developing tolerance and dependence is not to take G for more than 2 days in a row.

Withdrawal from G, if someone is addicted, can be very dangerous without medical support — so advise against people withdrawing on their own.

G is often thought of as the most dangerous chemsex drug and is linked to the most deaths. It is famous as “K.O. drops” as it is used to knock people out in bars or clubs, so the advice is for people to never leave their drinks alone. The difference between a  dose that has the desired effect and a dose that will kill is very small, and the advice is to never use G at saunas or whilst alone.

G with other drugs


It’s very risky to mix G with other depressant drugs (downers) such as alcohol and tranquilisers – but also ketamine or antihistamines (used in allergy medicines). Their combined action can dangerously slow down a persons breathing or cause a long ‘G sleep’.

Also known as ‘going under‘, G sleep isn’t sleep at all but a state of unconsciousness. A fit, coma or death can possibly follow. Even drinking booze a few hours earlier can leave enough of it in someones system to risk a collapse.

HIV drugs

G can also interact with some HIV medication, causing dangerously high levels of GHB and a bigger risk of collapsing.

Useful information to know and share 

  • If someone’s getting drowsy from GHB/GBL, don’t let them fall into G sleep – they’re not ‘sleeping’, they’re unconscious and may not wake up. Try to keep them awake and moving until the effects wear off or medical help arrives.
  • If G knocks someone out, to stop them choking on their own vomit they should be laid on their side, in the recovery position, not on their back.
  • If someone isn’t feeling well or can’t be woken up, get medical help straight away. There’s always a risk of sudden death if someone’s unconscious. You’ll be in a lot more trouble if you don’t get help and then have a dead body on your hands.
  • If you’re not going to get medical help put the person in the recovery position, sit with them and regularly monitor their pulse and breathing.

G should definitely be avoided if you have:

  • high or low blood pressure
  • epilepsy
  • convulsions
  • heart or breathing problems.

Next module: Crystal meth

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