GHB

GHB (gamma-hydroxybutyric acid or gamma-hydroxybutyrate) is a naturally occurring fatty acid found in the human body, where it is involved in the production and metabolism of the neurotransmitter GABA (gamma-aminobutyric acid). It was introduced as a medicine in the 1960's and was occasionally used for its anaesthetic and anxiolytic properties. Nowadays it is mainly prescribed as a hypnotic (sleep-inducing drug) for people suffering from cataplexia, and (in Austria and Italy) as a replacement drug in the treatment of alcoholism.

GHB is also widely used for its recreational effects, either in the form of GHB salt crystals or one of its prodrugs (i.e. compounds that the body itself converts to GHB), most notably GBL (gamma-butyrolactone). Another prodrug is 1,4-butanediol, which is also converted into GHB in the body, albeit not as quickly as GBL is. Both GBL and 1,4-butanediol are strong organic solvents that must be diluted in water to avoid causing chemical burns to the skin and mucous membranes. GHB should also be diluted, as the salt may contain traces of strong bases (alkali) left over from production. GHB, GBL and 1,4-butanediol are all listed as illicit drugs.

GHB produces an alcohol-like drug experience, being mildly stimulating at moderate doses and more sedative at higher doses. Very high doses cause one to abruptly fall into a deep sleep that normally lasts for a few hours, although overdoses can lead to a coma. GHB can be very difficult to dose due to a steep dose-response curve, i.e. increasing the dose by a small amount leads to a disproportionately large increase in effect intensity. For this reason, doses should always be measured out exactly using a medical syringe or measuring pipette, and new batches tested in small dose increments. It is also easy to think that the drug itself is wearing off once the sedative effects give way to mild stimulation, leading some to redose the drug too early and end up heavily sedated or fast asleep, so it is wise to keep track of time if/when redosing (more on this below). Stomach contents can affect how quickly and intensely GHB's effects are felt, so it is best to avoid eating right before taking GHB; otherwise, the effects may be delayed, in which case it is best to avoid redosing.

Neither GHB, GBL nor 1,4-butanediol are particularly harmful to the body's organs. However, since GHB is a depressant, overdoses – and especially combinations with other depressants – can be fatal. Most GHB-related deaths have involved simultaneous use of GHB with alcohol and/or other depressants, which carries a significant risk of respiratory arrest and unconscious vomiting, both of which can be fatal unless treated immediately. Stimulants, meanwhile, partially counteract the effects of GHB and delay its full effects until the stimulant effects have worn off. This means that unless one pays close attention to dosages, one may end up inadvertently overdosing on GHB while on a stimulant and not realize until the stimulant wears off, at which point the overdose effects abruptly kick in. Frequent, heavy use of GHB over time can lead to withdrawal symptoms similar to those of alcohol dependence, including a risk of potentially lethal epileptic seizures upon abrupt discontinuation of the drug.

Please see our 10 general rules for sensible drug use. You should also be mindful of the following:

• Avoid taking GHB if you have epilepsy or have previously had a drug-related epileptic seizure.

• Never take GHB while also using alcohol, opioids, benzodiazepines (benzo's) or z-hypnotics (zopiclone, zolpidem). These combinations quickly turn lethal.

• Be very careful if taking GHB on the way down from a stimulant drug, and avoid combining GHB with short-acting stimulants like cocaine.

• Be careful if combining GHB with psychedelics or dissocatives, as this can lead to confusion and vomiting.

• Always measure out your dose with a medical syringe/pipette, graduated cylinder, or some other precise equipment – never a soda bottle cap!

• Avoid daily or otherwise frequent use of GHB. If you find yourself needing higher doses than before, take a long break from GHB altogether. Tolerance puts you at higher risk of lethal overdose!

• If you have a GHB solution of unknown strength, never take more than 2 milliliters at a time. If you have GBL of unknown strength, never take more than 1 milliliter at a time.

• If you have GHB in a liquid solution, always shake the bottle well before measuring out your dose.

• Avoid taking GHB if you have just eaten, as this can delay the effects. If you do not notice a dose that should give you a noticeable effect, wait for at least an hour – do not take more!

• If you are inexperienced with GHB, wait at least two hours between each dose (if redosing) and avoid taking more than three doses in one session.

• If you are experienced with GHB and want a more sustained high, you can redose with half of your initial dose at one-hour intervals. If you find the effects getting stronger, increase your dose interval to 90 minutes, and then gradually adjust it back as needed.

• Avoid taking GHB alone, and make sure that someone else knows you are taking GHB and what to do in case you fall asleep. Never take GHB with people you do not trust!

• Never give GHB to anyone who does not know how it works, or whom you suspect will combine it with alcohol or other depressants.

• Avoid storing GHB in such a way that others (e.g. roommates, children) can mistake it for a normal beverage.

• If you notice withdrawals after frequent use of GHB, you should gradually reduce/step down your dose over several weeks. If you do not have enough GHB to do this, see a doctor ASAP.

• If someone falls asleep after taking GHB: place them in the recovery position (aka left lateral position), ensure their airways are open and unobstructed, and watch their breathing. If you are either inexperienced in dealing with GHB overdoses, OR you cannot rule out that the person in question has also been using other depressants like alcohol, OR you notice that their breath slows to less than eight breaths per minute, call an ambulance.

We employ a five-step risk scale with values ranging from "very low" to "very high" within six categories: Acute toxicity, Long-term toxicity, Dependence, Cognitive problems, Unpleasant events, and Interactions.

These values are based on qualitative reviews of available knowledge, and should only be viewed as guidelines. They are also relative, so a score of "very low risk" does not mean the substance is risk-free. The scale assumes users are normal, healthy individuals; beware that even drugs which are well-tolerated by most people may nevertheless be harmful to some users. It also assumes normal use patterns; that is, if a given drug is only harmful when used in a certain way, yet is almost never used in that way, then the drug will be considered less harmful compared to a similar drug which is commonly used in a harmful way.


ACUTE TOXICITY

⦿⦿⦿⦾⦾ (Moderate risk)

The difference between a recreational and a hypnotic (sleep-inducing) dose of GHB is very small. Although the vast majority of GHB-related deaths are due to combinations with other drugs, there are reports of lethal overdoses from GHB alone [17,23]. Oral doses of 100 mg GHB per kg of body mass, as well as intravenous doses of 70 mg/kg, have been administered without any negative effect on vital functions; early tests of GHB's anaesthetic potential evidently involved intravenous administration of up to 140 mg/kg [16,20–22].

Although the cause of death in lethal overdoses is respiratory failure, GHB actually has a minimal effect on respiration at medically relevant doses, hence its initial use as an anaesthetic [15,19,22]. GHB causes one to breathe more deeply, so that oxygen uptake is maintained even though one is breathing slower [8,15,16]. In animal experiments, this mechanism is observed all the way up to a lethal dose with GHB alone, but quickly fails when combined with alcohol in both animals and humans [9,11,24]. The risk of respiratory failure due to overdose may be affected by usage patterns: chronic GHB users develop a considerable tolerance to the recreational and hypnotic effects, but not to the antirespiratory effect [10]. This means that heavy users who require higher doses to achieve their desired effect are at greater risk of harmful or lethal overdoses [22].

A GHB overdose commonly leads to users abruptly falling asleep, after which it is impossible to wake them up for the first couple of hours. Although the sleep itself is temporary, and even though they are breathing well, they may still suffocate to death if their breathing is somehow obstructed. There is also a serious risk of users choking to death on their vomit if they lie on their back during a GHB overdose, since it is not uncommon to vomit from too much GHB, especially in combination with alcohol [21,24]. For this reason, anyone who has fallen asleep after taking too much GHB must be placed in the recovery position and monitored closely to ensure they continue breathing. If there is any doubt about whether they have also consumed alcohol or other depressants in addition to GHB, or if they begin to breathe slower than eight times per minute, call an ambulance right away.

GHB overdoses are normally not treated with any antidotes, and most cases do not require intubation or mechanical ventilation, even with concomitant use of other drugs [17]. However, monocarboxylate-transport-inhibitors (MCTi's) like diclofenac have been used to reverse GHB's effects in animal experiments, and the central nervous system (CNS) stimulant doxapram has been used to counteract the CNS depressant effects of GHB in at least one comatose patient [9,12,13]. In some drug use environments, amphetamine is used to wake people out of GHB overdoses, but this is risky from a medical perspective [6].


LONG-TERM TOXICITY

⦿⦿⦾⦾⦾ (Low risk)

GHB occurs naturally in the human body and is not especially toxic to its organs. Animal experiments involving rats have nevertheless shown neurotoxic effects upon administration of low doses over a long time, but this effect is not seen in high doses, and it is unclear whether the results apply to humans. GBL and 1,4-butanediol appear to also have low toxicity to the body's organs, even though 1,4-butanediol does produce some harmful yet short-lived metabolites. GHB obtained illegally can, however, contain traces of caustic lye (sodium hydroxide) left over from the manufacture process, which can cause chemical burns. Products containing GBL or 1,4-butanediol may also contain other chemicals, which carry their own risks.

DEPENDENCE

⦿⦿⦿⦾⦾ (Moderate risk)

Compared to to alcohol, GHB has a less severe hangover, improves sleep rather than worsening it, and is less toxic to the body. Because of this, it can be tempting to frequently take GHB instead of alcohol. However, frequent use of GHB can lead to withdrawal symptoms similar to those of alcohol dependence. Mild withdrawal is marked by irritability, anxiety, insomnia, and tremors, while more severe withdrawals may include psychoses and epileptic seizures. Going "cold turkey", i.e. abruptly quitting GHB after frequent heavy use, can lead to a medical or psychiatric emergency. This is why it is crucial to gradually step down from a heavy use pattern or dependence on GHB if one wishes to quit. In severe cases, withdrawal symptoms may need to be treated with baclofen and benzodiazepines as part of a drug replacement therapy program [1].

COGNITIVE PROBLEMS

⦿⦿⦾⦾⦾ (Low risk)

A series of studies found that using GHB as a hypnotic (sleep-inducing drug) is associated with improved cognitive function [25]. Although this is largely attributed to GHB's effect on sleep quality, which is known to greatly affect cognitive function, it also indicates that GHB does not have any significant negative effects on cognition [25]. Crucially, however, these studies involved administering GHB twice per night. Taking only a single dose, meanwhile, can paradoxically worsen overall sleep dividends: although sleep quality is improved, sleep duration may be reduced due to the sedative effects of GHB giving way to stimulation after only a few hours. This ultimately leads to lack of sleep, which does impair cognitive function over time.

Non-lethal GHB overdoses can indirectly lead to cumulative brain damage as a result of bodily organs being deprived of oxygen while sedated, mainly due to partially obstructed airways or simultaneous use of other CNS depressants.

UNDESIRABLE EVENTS

⦿⦿⦿⦿⦿ (Very high risk)

As mentioned, an overdose of GHB can lead to users abruptly falling asleep for 2-3 hours, during which time they cannot be woken up. This means GHB use carries a major risk of being subjected to sexual assault, robbery, or other forms of exploitation. It also means that activities involving cold weather or bathing carry a serious risk of hypothermia or drowning. You should therefore never use GHB in unsafe places or with people you do not know or trust, and there should always be someone nearby who can watch over you in case you fall asleep.

GHB inhibits impulse control and can thus lead to boundary-breaking behavior, especially in combination with other drugs. Stimulants in particular can counteract the hypnotic effect and enhance the stimulating effect of GHB, causing one to remain awake and able to do things even after taking too much GHB. However, users commonly report feeling more clear-headed on GHB than they do on alcohol, and someone under the effects of GHB may be mentally present despite almost falling asleep.

At higher doses, GHB interferes with motor skills and coordination, leading to a higher risk of accidents in situations where bodily control and balance are needed.

GHB can trigger seizures in people diagnosed with epilepsy, and is therefore contraindicated for use as a sleep aid in this cohort.

INTERACTIONS

⦿⦿⦿⦿⦿ (Very high risk)

Combining GHB with alcohol, opioids, or other CNS depressants/sedatives greatly increases the risk of overdosing on GHB, as well as increasing the risk of respiratory arrest and brain damage in case of an overdose [18,11]. If someone is unconscious and you suspect they may have taken another depressant (e.g. alcohol, benzodiazepines or opioids) in addition to GHB, call an ambulance immediately!

CNS stimulants counteract the depressant effects of GHB until the stimulant wears off. This can lead to situations where someone on stimulants ends up taking more GHB than they could safely handle if they were not on a stimulant, only to later suffer an overdose reaction once the stimulant wears off and the full effect of the GHB dose kicks in. This risk is especially high for simultaneous use of GHB and short-acting stimulants like cocaine or mephedrone, but also when taking GHB towards the end of the stimulant high with the goal of softening the come-down.

Interactions between GHB and other legal medications, see Felleskatalogen. Note that GBL and 1,4-butanediol may have additional interactions not listed for GHB, as these are metabolized into GHB by enzymes that are not involved in the metabolism of GHB. These interactions have not yet been fully documented.

DOSAGE

Dosing GHB of unknown concentration:

If the concentration of a GHB solution is unknown, the solution can be carefully boiled in a pot until all the water has boiled off and only the dry salt remains. This can then be weighed and dissolved into a new solution whose concentration is known. This method should not, however, be used for GBL or 1,4-butanediol, as these are volatile substances and significant amounts would evaporate with the water.

If you decide to use a solution of unknown concentration, make sure to start with a small dose measured out carefully using a syringe, graduated cylinder, or other precise measuring device. The first dose should be no more than 2 ml. (See different rule for GBL below.)

After dosing, wait until you feel an effect, then wait at least another two hours before you take any more. If you want to increase the dose, this should be done very carefully, since even a small increase in dose can lead to a very large increase in effect [3].

Dosing GHB of known concentration:

Once you know the concentration of your solution and have found a dose that works for you, you can maintain the desired drug effects in one of two ways:

If you are inexperienced with GHB, you should wait at least two hours between each dose and ensure that no redose is larger than the initial dose. You should also avoid taking more than three doses in total over the course of one session.

If you are more experienced, you can take half of your initial dose at one-hour intervals. It is best to use a timer so as not to redose too early. If you notice the effects getting stronger after a few rounds, try extending the dosage interval to 90 minutes.

Dosing GBL:

1 ml pure GBL is equivalent to roughly 1.7 g of pure GHB salt. If the concentration is unknown, the first dose should be no more than 1 ml.

Dosing 1,4-butanediol:

1 ml pure 1,4-butanediol is equivalent to roughly 1 g of pure GHB salt. If the potency/concentration is unknown, the first dose should be no more than 2 ml.

FORMAT

GHB is usually sold as a solution of GHB dissolved in water. Less commonly, it may be found as a dry salt in powdered form. Unless stored in an airtight container, the salt will quickly absorb moisture from the air, turning it into a slimy paste and making it more difficult to weigh out correctly due to the added mass of the water.

For someone with no tolerance to GHB, a recreational dose will typically be between 1.5 and 2 grams of the dry salt, depending on bodyweight and desired effects.

Note: since GHB, GBL and 1,4-butanediol are all more dense than water, they will sink towards the bottom of a solution over time. Make sure to always shake the bottle well before measuring out a dose!

ROUTE OF ADMINISTRATION

GHB, GBL and 1,4-butanediol are nearly always ingested (swallowed), usually mixed into some kind of beverage. GBL can also be taken in the form of large gelatine capsules. Besides ingestion, no other intake routes are in widespread use.

MECHANISM OF ACTION

GHB occurs naturally in the human body. It is both a metabolite of and a precursor to GABA. Like GABA, GHB acts as a neurotransmitter, and mainly binds to the brain's GHB receptors and GABA-A subreceptor α4βδ [1,2]. When GHB is used recretionally and its concentration in the bloodstream gradually increases, activation of GABA-B receptors also increases steadily [1]. It is hypothesized that GABA-B receptors, and to a lesser degree GHB receptors, are chiefly responsible for GHB's effects on the brain, which involve higher release of the neurotransmitters GABA, dopamine, and glutamate [2].

DURATION

The full effects of a dose of GHB are normally felt after 40 to 60 minutes, depending on the size of the dose, and the main drug effects normally go away after 1.5 to 2 hours. At high doses, however, the sedative effects may last for significantly longer, up to several hours [3].

GBL acts much faster than GHB, with full effects kicking in after only 10 minutes, while 1,4-butanediol acts roughly half as quickly as GHB.

SUBJECTIVE EFFECTS

GHB typically produces feelings of euphoria and bodily comfort. The effects are somewhat similar to those of alcohol, although many users report feeling more clear-headed on GHB than they normally do when tipsy or drunk. Like alcohol, GHB reduces anxiety and lowers inhibitions, making users more prone to uncritical or impulsive behavior. Many GHB users also report enhanced feelings of love and connection to others, somewhat reminiscent of MDMA. It is also popularly used in connection with sex, where it is reported to enhance feelings of sexual pleasure.

SIDE-EFFECTS

GHB greatly affects motor skills, balance, and coordination, often leading to unsteady walking and stumbling, especially at higher doses. Because of the small difference between a recreational dose and a hypnotic dose, if someone either takes too much or redoses too early, they can suddenly become drowsy and fall asleep much earlier than they had planned. High doses of GHB can also lead to nausea and bowel discomfort.

GHB normally does not come with an uncomfortable hangover. However, it is common to feel very awake for a while after the effects wear off (although some people subsequently get very sleepy again after this), which can negatively impact sleep if GHB is taken late at night. This is incidentally why GHB, when prescribed as a sleep aid, is supposed to be taken twice per night. Some users report a dry mouth and dry eyes the day after taking GHB. Some also experience bedwetting after taking hypnotic doses of GHB.

GHB, GBL and 1,4-butanediol are all listed as illicit drugs in Norway. This means it is punishable by law to use, possess, acquire, sell/give away, manufacture, store, import, export or otherwise distribute them without a special license for medical or scientific research purposes.

The limit for how much GHB, GBL or 1,4-butanediol one can acquire or possess for personal use and still receive only a fine, as opposed to a prison sentence, is currently set at 100 ml of solution. In case of import for personal use, such as ordering via mail from abroad, the limit is set to 50 ml of solution. No limit has yet been established for GHB salt in powdered form, but 100 ml of GHB solution of normal strength is roughly equivalent to 50 g of dehydrated salt.

GHB for medicinal use requires a valid prescription (reseptgruppe A).

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