Where the substance comes from
Ketamine is a veterinary and human anaesthetic, diverted from legal medical supply or made in South-East Asia. GHB is synthetic; GBL, its industrial precursor, is a solvent sold as a stain remover or wheel cleaner, which the body converts to GHB within minutes — the same substance, more concentrated and less controllable.
A little history
Ketamine was synthesised in 1962 by Calvin Stevens at Parke-Davis as a replacement for phencyclidine (PCP), judged too delirium-inducing; tested on volunteer prisoners in 1964 and approved in 1970, it became the anaesthetic of the Vietnam battlefields because it neither drops blood pressure nor stops breathing. It is still on the WHO list of essential medicines. Its diverted use began in the 1970s on the American west coast, then in the clubs of the 1990s under the name "Special K". Since 2019 a nasal form, esketamine, has been approved for treatment-resistant depression.
GHB has an older history: synthesised in 1874 by the Russian chemist Alexander Zaytsev, it was only studied in 1960-1961 by Henri Laborit in Paris, who was looking for an anaesthetic close to the neurotransmitter GABA. Sold as a bodybuilding supplement in the 1980s, banned by the FDA in 1990 after comas, it became in the 1990s the "date-rape drug" of the news, then the drug of chemsex and clubs, often in the form of its industrial precursor, GBL.
GHB is controlled internationally under the 1971 Convention on Psychotropic Substances (GOV.UK, 2013), while ketamine is controlled country by country; both have kept a legitimate medical use, which explains why they circulate easily.
The forms it takes
- Ketamine: white powder, snorted; more rarely an injected solution.
- GHB: salty liquid or powder, swallowed, measured by pipette or bottle cap.
- GBL: colourless liquid with a chemical taste, extremely concentrated. One millilitre too many is the difference between the intended effect and coma.
What the user is looking for
With ketamine, dissociation: the body recedes, sensation distorts, time comes apart. With GHB, an effect close to alcohol without the tiredness: euphoria, disinhibition, a sought-after aphrodisiac effect. Both are common in party settings and in chemsex.
Immediate unwanted effects
- Ketamine: loss of coordination and bearings, falls, inability to speak or move (the K-hole), vomiting with a risk of inhalation, acute anxiety.
- GHB and GBL: the dose-response curve is almost vertical. Half a millilitre separates disinhibition from coma. The G-hole is abrupt loss of consciousness, with muscle relaxation, vomiting and possible respiratory arrest. Alcohol multiplies the risk.
- GHB can be slipped into a drink without the person knowing: colourless and fast acting, it partly erases memory. Yet French national surveys of drink spiking rarely find it: sedative medicines dominate (59.6% of the substances mentioned in 2024), and MDMA is the single substance most often involved (ANSM, 2026). If in doubt, emergency departments have an appropriate testing pathway: go quickly, because detection windows are short, often under twelve hours for GHB.
Medium and long-term risks
Regular ketamine destroys the bladder: frequency, pain, bleeding, sometimes a bladder reduced to a few tens of millilitres and surgery in very young people. It also causes violent abdominal pain and memory problems. Regular GHB use can lead to dependence and a severe withdrawal syndrome (Drogues Info Service) — anxiety, agitation, tremor, insomnia, hallucinations, sometimes delusional episodes: stopping is best prepared with medical help rather than alone.
How to spot use
Small bottles of colourless liquid, pipettes or needleless syringes, waking with no memory of the end of the evening, unexplained falls, urinary symptoms in a young adult, brief repeated disorientation.
Why the effect is stronger in adolescents
At the same dose in a lighter body, the concentration reached is higher in an adolescent than in an adult. More importantly, the reward circuit matures well before the prefrontal cortex that is supposed to restrain it: the pull to repeat is stronger and the brake weaker, which markedly shortens the gap between first use and problem use. Use established before eighteen multiplies the risk of adult dependence whatever the substance — including legal ones such as the caffeine in energy drinks, alcohol or nicotine.
When to call an ambulance without hesitating
Loss of consciousness, seizures, severe confusion, slow or irregular breathing, blue lips, chest pain, very high temperature, uncontrollable agitation, suicidal thoughts. In those situations call the emergency services and say what was taken: treatment depends on it.