Opium is a natural substance extracted from the seed pods of the opium poppy (Papaver somniferum) that has been used for thousands of years primarily to relieve pain, treat diarrhea, and manage coughs. Today, its role in medicine is mostly indirect: the alkaloids extracted from opium serve as the chemical foundation for a wide range of prescription painkillers and other drugs collectively known as opioids.
What Opium Actually Contains
When the unripe seed pod of an opium poppy is scored with a blade, a milky white latex oozes out and dries into a sticky brownish resin. That resin contains dozens of active compounds called alkaloids, and the proportions vary depending on the plant variety and growing conditions. Morphine is the most abundant, making up roughly 8 to 25% of the dried latex by weight. Codeine accounts for about 1 to 6%, noscapine (a cough suppressant) about 4 to 15%, and papaverine (a muscle relaxant) about 0.5 to 5%.
These alkaloids work by binding to opioid receptors in the brain, spinal cord, and gut. The most important of these is the mu receptor, which morphine targets with high affinity. Activating mu receptors triggers powerful pain relief, feelings of euphoria, sedation, and slowed breathing. Other receptor types (delta and kappa) contribute additional effects like mood changes and altered pain processing. This receptor system is the reason opium has been so effective as a medicine, and so dangerous as a substance of misuse.
Historical Uses Across Civilizations
The Sumerians in ancient Mesopotamia were among the first people to cultivate opium, calling the poppy the “plant of joy.” Ancient Egyptian and Mesopotamian texts describe using it for pain relief. In the Hippocratic tradition of ancient Greece, opium poppy was a frequent ingredient in herbal remedies, prescribed for insomnia, anxiety, and chronic pain. For most of recorded history, opium was one of the few truly effective tools healers had against severe pain, and it remained central to Western medicine well into the 19th and early 20th centuries.
Modern Medical Applications
Raw opium itself is rarely prescribed today. Instead, its alkaloids are extracted and refined into specific medications, or used as starting materials to synthesize newer drugs. Here’s how opium’s components show up in modern medicine:
- Morphine remains a frontline treatment for severe pain, particularly after surgery, during cancer care, and in end-of-life settings. It is extracted directly from opium.
- Codeine, also extracted directly, is used in lower-strength pain relievers and prescription cough medicines.
- Thebaine, another opium alkaloid, is not used on its own but serves as the chemical starting point for manufacturing oxycodone, oxymorphone, hydrocodone, hydromorphone, and buprenorphine.
- Papaverine is occasionally used as a smooth-muscle relaxant, particularly for blood vessel spasms.
Synthetic opioids like fentanyl, methadone, and tramadol don’t come from the poppy plant at all but mimic the way opium’s natural compounds interact with opioid receptors. The entire class of drugs, whether natural, semi-synthetic, or fully synthetic, traces its pharmacology back to the effects first observed with opium.
Opium Tincture for Diarrhea
One of the few preparations of opium still used in its relatively whole form is opium tincture, a liquid containing the equivalent of 10 mg of morphine per milliliter. It is prescribed specifically for diarrhea, particularly severe or chronic cases that don’t respond to standard treatments. It has an orphan drug designation for chronic diarrhea in people with short bowel syndrome. Opioids slow the movement of the intestines, which is why constipation is one of their most common side effects. In this case, that side effect becomes the intended purpose.
How Opium’s Effects Work in the Body
When opium or any of its derivatives activate opioid receptors, several things happen simultaneously. Pain signals traveling through the spinal cord and brain are dampened, which is the therapeutic goal. But the same receptors also exist in the brainstem (where they slow breathing), in the gut (where they reduce motility), and in reward circuits (where they produce a sense of well-being or euphoria).
With repeated use, the body adapts. Receptors are pulled inside cells and recycled or broken down, a process that reduces their availability. This is the basis of tolerance: over time, the same dose produces a weaker effect, which pushes people toward higher doses. Physical dependence follows, meaning the body reacts with withdrawal symptoms when the drug is stopped. These overlapping mechanisms are why opium and its derivatives carry a high risk of addiction.
Risks and Side Effects
The most dangerous acute risk of opium and all opioids is respiratory depression. At high enough doses, the brainstem’s breathing centers slow to the point where oxygen levels drop dangerously low, which can be fatal. This is the primary cause of death in opioid overdoses.
Other common effects include:
- Constipation, which occurs at nearly every dose and doesn’t diminish much with tolerance
- Nausea and vomiting, especially with initial use
- Sedation and drowsiness
- Itching, caused by histamine release
- Hormonal disruption, including reduced testosterone and menstrual irregularities with long-term use
The risk of respiratory depression increases sharply when opioids are combined with alcohol, benzodiazepines, or other sedating substances.
Legal Status
In the United States, opium is classified as a Schedule II controlled substance by the Drug Enforcement Administration, the same category as morphine, codeine, and hydrocodone. Schedule II means the substance has accepted medical uses but carries a high potential for abuse and dependence. Possessing or distributing opium outside of authorized medical or research channels is a federal crime. Most other countries impose similarly strict controls.
Legal cultivation of the opium poppy for pharmaceutical purposes is tightly regulated. A handful of countries, primarily in the Southern Hemisphere and parts of Europe, are authorized to grow poppies under international treaty agreements overseen by the United Nations. The raw material is processed into pharmaceutical-grade alkaloids at licensed facilities and distributed to drug manufacturers worldwide.