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The molecular structure of GHB
  • GHB

    Gamma-hydroxybutyric acid (GHB) is found naturally in tiny quantities in the human body and other animals. The GHB that is available as a recreational drug or medication is manufactured but is still the same compound.


    Gamma-butyrolactone (GBL) 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, however, it is much rarer. It is likely to share the effects and harms of GHB.

    They are all central nervous system depressant drugs.

  • GHB is usually identified as a colourless, oily liquid but it is also encountered as a whitish powder. It is odourless and has a salty/soapy taste.

    GBL is a colourless, oily liquid that has a strong chemical smell and taste.

    GBL is used as a solvent for cleaning metal, paint stripping and glue removal.

    GHB and GBL are usually ingested orally by using a pipette or syringe to transfer a small amount of the liquid into another drink.

    Rarely, some people may inject GBL, but this is very dangerous.

    Some people may also snort GHB when it is in powder form. Again, this is rare and may make it harder to monitor dosage.

  • GHB works in the body in two ways to produce its effects.

    • Activates inhibitory GHB receptors in the brain, producing sedative effects and stimulating the release of dopamine and growth hormone.

    • Activates GABAB receptors in the brain, producing sedative effects.

  • 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 People under their influence can be chatty, outgoing, and giggly, although some others become withdrawn.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 two main medical uses.

    Xyrem, which consists of the sodium salt of GHB (sodium oxybate), is prescribed to treat excessive daytime sleepiness and cataplexy (sudden temporary muscle weakness), which are symptoms of narcolepsy.

    GHB is sometimes used to aid alcohol withdrawal, opioid withdrawal, treating fibromyalgia, essential tremor, ME, and other conditions. However, there is not yet enough scientific evidence to support its use in this way.

    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 overdose with GHB and GBL. This is because there is a very small difference between an enjoyable dose and a dangerous one. The steep dose response curve of the drugs also means that similar doses can be much more powerful on redosing. Overdose can lead to unconsciousness, depression of breathing, and brain damage. It is important to seek medical assistance as soon as possible if an overdose is suspected.

    The drugs may take longer to take effect than expected, and factors like stomach contents can make this time vary. This means someone who takes a second dose without having waited for the effects to reach their peak could be taking a big risk. GBL is also much more potent than GHB, so a smaller dose is required. 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.

    Sometimes, these drugs are purchased as a solution already diluted by some amount, other times they are pure. Pure GBL sold for industrial use is often prepared into a solution of known strength by the user by transferring a set amount of GBL into a set amount of water or juice, for example. Knowing the strength helps with getting the dose right. Weaker solutions of these drugs are less likely to cause accidental overdose. 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, leading someone to take an unintended overdose. Therefore, it is important to closely monitor any drinks containing GHB or GBL.

    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.

  • Any amount of GHB or GBL decreases a person’s ability to make sensible decisions. The drugs also reduce coordination, making simple tasks much more difficult. Care should be taken when crossing roads, for example, as it may be more difficult to judge distances of passing cars. Of course, driving after taking the drug would be particularly dangerous.

    Users can become confused, and less able to react appropriately to what is happening around them. Some become aggressive, which can pose a problem in hospital emergency units if a person is agitated and difficult to manage.

  • 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.

  • GHB and GBL should not be mixed with other drugs, or with each other.

    Mixing GHB or GBL with other drugs that depress the nervous system, such as alcohol, greatly increases the risks. Mixing with ketamine, opioids like heroin or methadonebenzodiazepines like diazepam, and other drugs that have sedating effects will also increase the risks.

    Combinations with stimulants like cocaine could also add risk, as 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 everyday 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 start within hours of the last dose. The difficulty of withdrawal varies. Some may struggle with insomnia, jitteriness, and low mood, for others, withdrawal can be life-threatening, requiring intensive care. People who are addicted to GHB/GBL should not attempt to suddenly stop using it without medical assistance, as this could be dangerous.

    Symptoms in the first days may include agitation, panic attacks, hallucinations, shaking, raised heartrate, and occasionally seizures and muscle breakdown. Depression, anxiety, and insomnia may continue for weeks or more.

  • 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 to accurately measure a dose. GHB, when sold as a solution, varies in concentration, so it is very important to know how strong the solution is, however, there may still be inaccuracies. Always start with a very small dose.

    Sensitivity to the effects may vary from person to person. If you buy or are given a pre-prepared solution 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?

    Never mix GHB or GBL with other drugs.

    Just a small amount of alcohol combined with GBL can have strong negative effects. A high proportion of those who experience negative effects after taking GBL have also been drinking alcohol or using other sedative 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 negative effects, seek medical assistance immediately. If they cannot be roused, put them into 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 to achieve the look they want. No studies have been conducted on the side effects or if there are any lasting benefits of using the drug for muscle growth.

    However, tolerance to GHB builds up fast when used daily. It becomes difficult to sleep without using ever-greater doses. Therefore, addiction can result. The benefits of daily GHB for bodybuilding are not proven, but the harms are clear; bodybuilders have suffered from serious addiction problems from their GHB use.

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