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Opium

Opium molecule structureOpium molecule structure

Opium is a naturally occurring mixture of opiate alkaloids obtained by drying latex from the seed pods of Papaver somniferum. It acts as a depressant1 and pain reliever,2 with morphine as its principal psychoactive constituent.3 Its alkaloid content varies between plants. Ancient civilizations used opium for medicinal and ritual purposes, including pain relief and sedation.4 Opium can cause addiction,2 and long-term use can lead to tolerance, dependence, and increased cancer risk.

Dosage & Duration

Log in Piru

Dosage

Doses are population estimates that vary widely between individuals.

Moderate333-500 mg

Duration

After Effects1-12 hours

Subjective Effects

Subjective Effects not written up yet

Reagent Testing

Expected colorimetric results for common reagent tests. Colors show reaction change over 1–2 minutes.

Marquis(MQ)
white → purple2
Mecke(ME)
white → green2 → black3
Mandelin(MD)
yellow2 → brown3
Ehrlich(EH)
white → pink1
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Pharmacology

Pharmacodynamics

Opium activates μ-, κ-, and δ-opioid receptors, with its principal psychoactive constituent, morphine, acting at μ-opioid receptors to reduce pain signaling. Activation of these G protein-coupled receptors opens potassium channels and inhibits the opening of voltage-gated calcium channels5, reducing neuronal excitability and neurotransmitter release. Opium also increases smooth muscle tone and reduces gastrointestinal motility.

Pharmacokinetics

Opium has poor oral bioavailability. For opium tincture, reported peak blood concentrations are 16-24 mg/ml, with total exposure (AUC) of 3237-6727 ng/ml.h. Its volume of distribution exceeds total body water, and protein binding varies between alkaloids from 20-60%, principally involving albumin and beta-globulin II. Metabolism includes conversion of opiate constituents to morphine followed by glucuronide conjugation. CYP2D6 contributes to metabolism, and genetic variation in this enzyme can alter the metabolic rate; opium is also listed as a CYP3A and CYP3A4 substrate. The reported half-life is 3-10 hours. Alkaloids are excreted in urine, with detection lasting longer after larger doses or repeated administration.

Interactions

Interactions not written up yet

An unlisted combination is an unknown one, not a safe one. Check a dedicated combination chart before mixing.

Check TripSit

Tolerance

Tolerance timelines are rules of thumb, not exact schedules, and vary widely between individuals and use patterns.

Full Tolerance
Regular opium use can result in tolerance.6 Some secondary effects tend to become less pronounced as tolerance develops with long-term use.

Harm Potential

Addiction & Dependence

Psychological

Opium can cause addiction.7 Its addictive effects involve μ-opioid receptor activation of dopaminergic neurons in the ventral tegmental area, increasing dopamine release in the nucleus accumbens.5

Physical

Regular opium use can lead to physical dependence and tolerance.7

Toxicity

Respiratory system

Opium can cause respiratory depression, hypoventilation, prolonged apnea, respiratory obstruction, pulmonary edema, and respiratory collapse.

Cardiovascular system

Opium can cause cardiac collapse.

Central nervous system

Opium can cause coma.

Endocrine and reproductive systems

Opium-related endocrine dysfunction can include reduced testosterone, loss of libido, impotence, amenorrhea, and infertility.

Gastrointestinal system

Opium can cause constipation, nausea, and vomiting.8

Carcinogenicity
Confirmed

Opium is an IARC Group 1 human carcinogen,9 with sufficient evidence that it causes cancers of the larynx, lung, and urinary bladder.10

Evidence Basis
Human EpidemiologicalPositive
Animal Models
None

History & Culture

Early cultivation and Mediterranean traditions

The earliest archaeological evidence of human use of opium poppies came from the Mediterranean region and dated to before 5000 BCE. Neolithic finds were reported in Switzerland, Germany, and Spain. At the Cueva de los Murciélagos burial site in Spain, large quantities of poppy capsules were dated…

Legality

International

Prohibited drug of abuse in most countries

Legal production exists in some countries for alkaloid extraction

By Country

Illegal2
United States flagUnited StatesIllegal
Canada flagCanadaIllegal

References

Citations

  1. Opium Pillow. DEA Museum (n.d.). https://museum.dea.gov/museum-collection/collection-spotlight/artifact/opium-pillow1
  2. Opium Consumption. International Agency for Research on Cancer (2021). https://publications.iarc.who.int/60012
  3. DARK Classics in Chemical Neuroscience: Morphine. ACS Chemical Neuroscience / PubMed (2018). https://doi.org/10.1021/acschemneuro.8b001501
  4. Feasibility of Using Mycoherbicides for Controlling Illicit Drug Crops: 3 Target Illicit Crops. National Academies Press (2011). https://doi.org/10.17226/132781
  5. Opium: Uses, Interactions, Mechanism of Action. DrugBank (n.d.). https://go.drugbank.com/drugs/DB1113012
  6. Opium. Alcohol and Drug Foundation (2026). https://adf.org.au/drug-facts/opium1
  7. DailyMed — OPIUM TINCTURE DEODORIZED- morphine tincture solution. DailyMed, National Library of Medicine (2025). https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=674a969a-707d-41a9-b7c3-b90cbf2909e312
  8. DailyMed—Belladonna and Opium Suppository Label. dailymed.nlm.nih.gov (n.d.). https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8301e76b-134a-43d2-a7dc-c600ccf2695c12
  9. IARC Monographs Volume 126: Opium Consumption. International Agency for Research on Cancer (2021). https://www.iarc.who.int/news-events/monographs-126-opium-consumption1
  10. Opium Consumption, IARC Monographs Volume 126 — Evaluation and Rationale. International Agency for Research on Cancer (2021). https://publications.iarc.who.int/_publications/media/download/6667/fc14843a03f138767db83b001a86dfe4910621e9.pdf1

Further Reading

  1. Presley & Lindsley 2018 - DARK Classics in Chemical Neuroscience: Opium, a Historical Perspective

Article Status

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