Opioids

Background

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).

Usage

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 species.

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).

Popularity

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).

Pharmacology

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.