GHB is gamma-hydroxybutyric acid. It is naturally found in tiny quantities in the body of  humans and other animals. The GHB that is available as a recreational drug or medication is manufactured but is still the same compound.


Gamma-butyrolactone is a GHB ‘prodrug’. This means that it is converted into GHB in the body, so it has very similar effects and harms.

1,4-BD (1,4-butanediol) is another GHB prodrug although this is much rarer. It is likely to share the effects and harms of GHB.

GHB is encountered in its ‘salt’ form, as a whitish powder or dissolved in water.

GBL is a liquid, available in some countries in the form of an industrial solvent for cleaning metal or removing spray paint from vandalised buildings.

The doses of GHB and GBL are different, and should be researched before use. Errors with getting the right dose can and do kill. The same dose has different effects on different people. What may be a normal dose for one user could be a dangerous overdose to another user.

Sometimes these drugs are bought as a solution already diluted by some amount, sometimes they are pure. Pure GBL sold for industrial use is often prepared into a solution of known strength, by transferring a set amount of GBL into a set amount of water or juice. Knowing the strength helps with getting the dose right. Weaker solutions of these drugs are less likely to cause accidental overdoses just as it is harder to accidentally get alcohol poisoning from beer than from vodka. It is less risky therefore to drink a dose of the drug diluted in a bottle of water over an hour than to drink the same dose in one go from the cap of a bottle of a strong solution. Often, small quantities of the drugs are added into something like water, cola or juice for drinking. The drugs, when consumed pure or almost pure, can taste very unpleasant or burn.

There is a danger of users losing track of drinks or bottles containing these drugs, allowing someone to take an unintended overdose.

These drugs are not known for being adulterated with other harmful substances, but this is always a risk. Even products sold as commercially available solvents may contain harmful impurities.

GHB is a nervous system depressant, which activates GABA receptors (which are also activated by alcohol), causing parts of the brain to become less excitable and responsive. It has a range of other effects too and seems to have stimulant activity at low doses. The addictiveness of the drug may be related to its effects on dopamine. Overall our understanding of the working of these drugs is incomplete.

Much like alcohol, these drugs are intoxicating nervous system depressants and are often used in a social context where they can make people happy and confident. People under their influence can be chatty, outgoing, and giggly, although some others become withdrawn. Like alcohol, it may make people say and do things they normally wouldn’t (reduces inhibitions). Some users find that for them, the drugs enhance sexual feelings. After a bit of GBL or GHB people start to lose the ability to concentrate and think straight.

As with alcohol, the depressant and euphoric effects become clearer at high doses. GBL and GHB are much more potent than alcohol however, meaning that only a small amount, one swig too many, can be enough to accidentally cross the line between joy and coma. Unpleasant effects like vomiting and confusion become more common as the dose, and risks of harm rise. Technically, GHB and GBL have a ‘steep dose-response curve’ which means that a second or third dose may have a much greater (and unexpected) effect than the first.

People can become dependent on GHB, GBL or 1,4 BD, so sometimes it is used more to relieve a craving, stop withdrawal symptoms or feel normal rather than to have fun. Some users find sleep is impossible without the drug. As with alcohol, GHB, and GBL are sometimes used as a way of dealing with problems or depression through the obliteration of all feeling.

Some people report feeling groggy or fuzzy-headed as an after-effect of the use of GBL or GHB. However, the after-effects are generally reported as milder than the after-effects (hangover) from an amount of alcohol that causes a comparable intoxication. This should not necessarily be seen as an advantage as easier recovery may be one of the aspects that allow some people to quickly become heavy users and addicts.

GHB has a couple of medical uses. Xyrem, which consists of the sodium salt of GHB, is prescribed to help narcoleptic people deal with symptoms of excessive sleepiness and cataplexy (sudden temporary muscle weakness).

The drug’s potential is being explored for use treating fibromyalgia, essential tremor, ME, alcohol withdrawal and other conditions. Much more research will be necessary to demonstrate that it could offer benefits over existing therapies.

Using GHB or GBL to self-medicate for any health issue puts you at risk of all the harm these drugs can cause, especially addiction. It is likely that these risks outweigh any potential benefits.


There is a particularly high chance of accidental overdose with GHB and GBL, because an extra half-millilitre of GBL or half-gram of GHB on top of a moderate dose can make you fall into a deep sleep where you could potentially choke to death on your own vomit. Knowledge of the recovery position and how to clear an airway could save lives. Slightly higher quantities can cause coma-like unconsciousness from which the user cannot be woken. Breathing becomes shallow, slow, and irregular or stops. This respiratory depression can easily kill or cause brain damage, (although most people who overdose will recover without lasting consequences). Large overdoses can also cause seizures, and interfere with or stop the heartbeat. Getting medical help fast is essential if you suspect that you or someone else has taken an overdose, or you find that someone cannot be woken.

The drugs may take a while to kick in compared to expectations and factors like stomach contents make this time variable. This means someone who takes a second dose without having waited for the effects to reach their peak could be taking a big risk. Second or third doses can have much bigger effects than the first dose because of the ‘steep dose-response curve’ of these drugs. To reduce risk of overdose users should only take smaller doses after their first dose, having given enough time to feel the effects reach their peak.

Any amount of GHB or GBL will decrease your ability to make sensible decisions or deal with dangers like crossing roads, as well as reducing your coordination. Of course, driving after taking the drug would be particularly dangerous. Users can become confused, and less able to react to what is going on around them. Some become aggressive and some people who end up in hospital emergency units after overconsumption can be agitated and difficult to manage. Violence and driving accidents can harm others who are not taking the drug as well.

GHB has been used as a tool to carry out sexual assaults. Though the moral responsibility is wholly with the assaulter and not the victim, everyone can reduce the risks of becoming a victim by not leaving drinks unattended, not accepting open drinks, and by reducing their drinking/use of other intoxicants. Also, you should never finish drinks that taste suspicious (especially if salty- GHB, or plasticky- GBL).

Although GHB or similar drugs may be used to spike drinks, a point to remember is that alcohol itself is by far the drug most likely to facilitate sexual assault and even in cases where GHB is involved alcohol is likely to be involved too.

Mixing GHB or GBL with other nervous system depressant drugs, alcohol being the most common culprit, makes it much more likely to cause unpleasant effects, harm and death. Ketamine and opiates/opioids like heroin or methadone, benzodiazepines like  diazepam, and other drugs that have sedating effects will all increase the risks.

Combinations with stimulants like cocaine could also add risk, especially if they make the user feel more awake than they would otherwise feel, allowing them to tolerate more GHB. If the stimulant then wears off more quickly than the GHB or GBL this could result in unexpected coma.

1,4-BD is broken down in the body by the same enzymes that metabolise alcohol, so taking these two together may be particularly unpredictable and risky.

GHB and GBL can be addictive, typically when the drugs are used regularly for a sustained period. Taking GHB or GBL every day results in increased tolerance and users may become dependent on it. Those dependent on GHB and GBL usually suffer from cravings, anxiety, low mood, and have trouble sleeping if they do not re-dose every few hours.

Withdrawal symptoms kick in within hours of the last dose, or if the dose is cut down. The difficulty of withdrawal varies. Some may struggle with insomnia, jitteriness and low mood, but others have such bad withdrawal that it can be life-threatening, requiring intensive care.  People with serious addictions to it should not attempt to suddenly stop using it without medical help. Symptoms in the first days may include agitation, panic attacks, hallucinations, shaking, raised heart-rate, and occasionally seizures and muscle breakdown. Depression, anxiety and insomnia may continue for weeks or more. It may be difficult to access medical services that can help beat such an addiction because there may not be specific plans in place for the management of GHB/GBL withdrawal.

There has not been research identifying any long-term health harms caused by consuming these drugs aside from the very significant ways that addiction itself can severely impact your quality of life. However, there have not been many people living with dependence on these drugs for many years, so the lack of existing evidence is not proof of a lack of harm.

How much are you taking?

Extreme caution should be used when measuring doses. Pipettes are often used. GHB, when sold as a solution varies in concentration, so it is very important to know how strong the solution is, although you should not rely on it being the strength you have been told. Always start with a very small amount and work up. People have ended up coming round in hospital after swigging from the bottle directly. Different people will be more or less sensitive to the effects, just as with alcohol. If you buy or are given a pre-prepared solution of any of these drugs, the risks of accidentally taking too much is especially high. Taking an unmeasured dose of an unknown solution is very risky, even if it seems like a small amount. Measuring out doses millilitre by millilitre using a pipette, and starting with a small dose, reduces the risk.

Are you taking GHB or GBL on its own?

A very little alcohol combined with GBL can have a powerful and negative effect. A high proportion of those who collapse after taking GBL have also been drinking, or using other sedating drugs.

Are you taking responsibility over the risks you face?

These drugs may be carried in quantities enough for several overdoses, so it may be safest to prepare in advance the quantity you wish to take in one session so that when intoxicated, you can only take up to an arranged limit.

Friends should always look out for each other – if someone is suffering bad effects, then seek medical assistance immediately. If they cannot be roused, put them in the recovery position until you can get help.

Is GHB/GHB safe as long as it isn’t mixed with alcohol?

No. Many overdoses, deaths and harmful consequences have occurred with just GHB and GBL alone, although taking it with alcohol does radically increase the risks. People can develop severe addictions to GHB and GBL too.

Is GHB/GBL good for bodybuilding?

GHB and GBL are probably not effective ways of achieving bodybuilding aims. It is certainly not worth the risks of trying it out.

Before GHB began to be outlawed in many countries, it was promoted as a supplement for bodybuilders. This marketing was based on research showing that it stimulates the release of growth hormone during deep sleep. There have not been any studies that directly demonstrate that it helps bodybuilders achieve the look they want. It is not an anabolic steroid. No-one has studied the side-effects or the practical questions of whether you can stop taking it and keep any benefits. However, tolerance to GHB builds up fast when used daily. It becomes difficult to sleep without using ever-greater doses. Addiction can result. When deciding whether to use a drug, whether as a recreational user or a prescribing doctor, harms are balanced against benefits. The benefits of daily GHB for body-building are questionable but the harms are clear; bodybuilders have suffered from serious addiction problems from their GHB use.

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