Where the substance comes from
Two origins coexist. Natural and semi-synthetic opioids come from the poppy: morphine, codeine, heroin, historically grown in Afghanistan and, since Afghan production collapsed, increasingly in Myanmar and Mexico. Synthetic opioids — fentanyl, carfentanil, nitazenes — come out of laboratories and depend on no harvest: a few kilograms replace tonnes of heroin, which explains both their spread and their lethality. A counterfeit tablet sold as an ordinary painkiller can contain a fatal dose of fentanyl, and two tablets from the same bag can contain very different doses.
The third source is medical: prescribed painkillers later diverted, tramadol and codeine bought without a prescription in some countries, cough syrups.
A little history
The poppy was cultivated in Mesopotamia 5,000 years ago — the Sumerians called it the "joy plant" — and opium appears in the Egyptian Ebers papyrus. Laudanum, a tincture of opium in alcohol, was popularised by Paracelsus in the sixteenth century and by Sydenham in the seventeenth; it was given to infants to make them sleep. The Opium Wars (1839-1842 and 1856-1860) forced the British trade in Indian opium on China, with millions of dependants.
Chemistry changed the scale: morphine was isolated in 1804 by the young German pharmacist Friedrich Sertürner, the hypodermic syringe appeared in 1853, and the American Civil War left tens of thousands of dependent veterans — the "soldier's disease". Heroin, synthesised in 1874, was marketed by Bayer in 1898 as a "non-addictive" cough remedy. Codeine (1832), methadone (Germany, 1937-1939), naloxone (1961), buprenorphine (1966) and fentanyl (Paul Janssen, 1960) completed the family. The 1912 Hague convention opened international control.
The gravest crisis is recent: from 1996 the marketing of Purdue Pharma's OxyContin persuaded American doctors that strong opioids were safe for chronic pain; then came the heroin wave around 2010 and the illicit fentanyl wave from 2013, with more than 100,000 overdose deaths a year in the United States in 2021-2023. Europe, which developed substitution treatments from the 1990s, has so far been largely spared.
The forms it takes
- Powder (brown or white heroin), snorted, smoked off foil or injected.
- Tablets: diverted painkillers, or counterfeits containing fentanyl.
- Transdermal fentanyl patches, misused by chewing or extracting them — particularly dangerous, because a patch holds several days' dose.
- Codeine syrups, often mixed into soft drinks and drunk in company.
What the user is looking for
A wave of warmth and relief, physical and mental pain wiped out, a calm indifference. Many users describe not pleasure but the disappearance of suffering. Tolerance builds within weeks: the dose must rise to get the same effect, while the fatal dose does not rise in the same proportion.
Immediate unwanted effects
Nausea and vomiting, itching, severe constipation, pinpoint pupils, drowsiness. The danger is respiratory depression: breathing slows, becomes irregular, then stops. The signs of overdose are sleep from which the person cannot be woken, slow or snoring breathing, blue lips and nails, tiny pupils.
What to do in an overdose
Call an ambulance. Put the person on their side. Give naloxone if you have it: an antidote sprayed up the nose, harmless even if the diagnosis turns out to be wrong, and available without prescription in a growing number of countries. Stay until help arrives: naloxone wears off sooner than the opioid, and the breathing can fail again.
Medium and long-term risks
Established physical dependence, with a gruelling but not fatal withdrawal: diffuse pain, diarrhoea, sweats, anxiety, insomnia, over several days. Injecting adds abscesses, heart infections and transmission of HIV and hepatitis B and C through shared equipment. Overdose risk peaks after a period of abstinence — leaving hospital, leaving prison, finishing treatment — because tolerance has fallen while the habitual dose has not.
Effective substitution treatments exist, methadone and buprenorphine, which remove craving without intoxication and sharply cut mortality. They are prescribed long term, sometimes for years: that is not a failure, it is the treatment.
How to spot use
Very small pupils even in dim light, nodding off mid-conversation, injection marks at the elbow or elsewhere, long sleeves in summer, constipation, weight loss, blackened spoons, foil, syringes, money or objects disappearing. Analytically, morphine and heroin show in urine for two to three days; fentanyl and its analogues need specific tests, absent from ordinary dipsticks.
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, and nobody is prosecuted for calling to save someone.