Since the dawn of pain, creatures have long sought ways to mitigate the evolutionary warning signal. One of nature's most effective painkillers is opium, a highly addictive, milky latex extracted from poppy plants.

The poppy's medicinal origins stretch to at least the Neolithic Age, which ended about 4,000 years ago; archaeological evidence suggests the plant initially grew near the Mediterranean. (Listen to humanity's history of opium use).


Opium made its way via trade and cultivation across several ancient civilizations, including Egypt, Rome, and Baghdad, where it was used as a general anesthetic and painkiller.

Opium as a medicine was often applied topically or ingested as a powder, syrup, or tincture—a mixture involving alcohol and sometimes other spices.

Its consumption slowly shifted from eating to smoking with the rise of tobacco, increasing the drug's social usage, euphoric effects, and the likelihood of addiction (See the Opium Wars).


Opium consumption took another turn in the 1800s after the advent of the hypodermic needle and the successful isolation of one of opium's many active ingredients, a venture undertaken in an attempt to address the drug's unpredictable potency.

This isolated alkaloid—an organic nitrogen-containing compound, such as caffeine or psilocybin, produced by plants and fungi to guard against consumption, often with pronounced physical effects—was initially named "morphium" after Morpheus, the Greek god of dreams.

Injectable morphine was even more potent and fast-acting than its predecessors, making it an easy choice for doctors and pharmacists. (Hear about the US' first opioid crisis).

It also was more addicting, meaning its widespread usage led to widespread addiction—known then as "morbid craving"—and withdrawal symptoms.

Opiates to Opioids

At the turn of the 20th century, scientists developed heroin, a brand-name cough suppressant and reportedly a nonaddictive cure for opium and morphine addiction.

Within a few decades, the nonaddictive claim fell to the wayside as patients grew tolerant to the over-the-counter drug and demanded larger doses to address their health concerns (and avoid withdrawal symptoms).

Criminalization efforts to decrease the widespread use of opiates—naturally occurring drugs derived from the poppy—led to the creation of opioids, a term that refers to both synthetic and naturally derived opium variations, which were similarly marketed to the public as less addictive versions of their predecessors. (See Opioid Crisis).


Opioids are agonists that bind to and activate specific receptors throughout the body, causing pain relief, euphoria, and relaxation. (Hear why opioids are addictive).

When an opioid molecule slots into an opioid receptor, the body releases dopamine, a hormone and neurotransmitter associated with pleasure and memory, and suppresses the release of noradrenaline, a hormone and neurotransmitter involved in keeping the body alert and focused.

Noradrenaline, also known as norepinephrine, is also involved in regulating heart and breathing rates, meaning high doses of an opioid can cause breathing and heart rates to slow to dangerous levels.

Long-term use causes the body to become overly sensitive to noradrenaline, leading to withdrawal symptoms, including fever, muscle aches, and vomiting, possibly to the point of dehydration and death.

Paradoxically, opioids can also worsen pain, causing users to develop hypersensitivity as their bodies attempt to adapt to the loss or dulling of sensory feedback.

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Once in the body, opioids bind to naturally occurring opioid receptors typically used by endorphins to temper pain. They trigger the release of dopamine, a desire-related hormone, and decrease noradrenaline, a neurotransmitter involved in heart and breathing rate regulation, meaning high doses can slow these processes to dangerous levels. As the body adjusts, it decreases opioid receptors and increases noradrenaline sensitivity, relying on continued opioid use to maintain homeostasis.

Substance Abuse and Mental Health Services Administration

How does Narcan work?

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Naloxone, also known by the brand name Narcan, is an opioid-overdose reversal medication that typically begins working within a few minutes. Opioid use typically causes users to experience pain relief, euphoria, relaxation, and slowed breathing, sometimes to the point of suffocation. Naloxone, an opioid antagonist, attaches to opioid receptors without activating them, forcing opioid molecules out of their respective receptors and allowing users' breathing rates to normalize.

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Religious or medical use of opium derived from the poppy plant has stretched across Europe and Asia since at least 1,200 BCE. By the 16th century, humanity had come to see opium as more than medicine: it was a marketable product. This perspective also defines today's relationship with opioids, highly addictive painkillers at the heart of the deadly and ongoing epidemic planted by pharmaceutical companies.

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Heroin and synthetic opioids kill someone in the US every 16 minutes. Communities across the country have been ravaged by deaths, overdoses, jail time, and babies born with drug-related medical problems as opioid abuse became a typical feature of many American towns. This Pulitzer Prize-winning exposé, originally published in 2017, gives readers an inside look at how these drugs devastated communities around Cincinnati, Ohio.

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The origins of the US' ongoing opioid crisis are typically traced to the more than one billion prescription pain pills that flooded medicine cabinets between 2005 and 2019. This prescription opioid epidemic resulted in more than 210,000 fatal overdoses and set the stage for the ongoing crisis fueled by heroin and fentanyl. Using US federal data, this deep-dive maps out the surge in legally prescribed pain pills and related deaths county-by-county.

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State and local governments trying to address the opioid epidemic have sued organizations they believe started and supported the crisis. Companies that made, distributed, or contributed to sales of the highly addictive painkillers are expected to pay more than $50B in settlements. These settlements specifically state that at least 85% of settlement funds must be spent on addressing the epidemic, though where exactly the money is going is unclear.

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