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Opium

Nicknames: ‘Big O’, ‘Chinese molasses’
Last reviewed: October 2026

Description

Opium is the dried latex that exudes from the scored seed capsules of the opium poppy (Papaver somniferum). It contains a complex mixture of over 50 naturally occurring alkaloids, the most potent and abundant being morphine, codeine, thebaine, and papaverine.

Opium acts as a central nervous system depressant and potent analgesic, slowing down bodily functions, reducing pain, and producing a dreamlike state of relaxation. It is the direct botanical parent from which morphine, codeine, and semi-synthetic opioids (including heroin and oxycodone) are derived.

It has been cultivated and used by humans as an indispensable medicine and social relaxant for over 5,000 years, and opium poppy straw remains the primary global agricultural source for modern pharmaceutical analgesics today.

Desirable Effects

  • Deep physical relaxation and calm
  • Analgesia (effective pain relief)
  • Drowsy, dreamlike state of mind and reduction of emotional stress

Undesirable Effects

  • Nausea and dizziness
  • Headaches and confusion (especially at higher doses)
  • Constipation and urinary retention
  • Respiratory depression at excessive doses
  • Development of tolerance and physical dependence with sustained use

What does it look like?

Raw opium appears as a dark brown, black, or reddish-brown sticky gum, resin, or dried tar-like substance with a distinct, pungent, bittersweet herbal aroma. It is not widely circulating in UK recreational drug scenes, typically brought into the country in small personal amounts from cultivating regions such as Afghanistan, Iran, or Southeast Asia.

Method of Use

Smoked / Vaporised: Historically smoked using specialised pipes or vaporised through heat. The raw gum is heated to release opioid-rich vapours without combusting the plant matter.

Swallowed: Ingested orally in raw pellets or dissolved into traditional medicinal decoctions and tinctures (such as laudanum).

Note on injecting: Raw opium contains plant resins, fats, and insoluble matter and cannot be safely injected. Attempting to inject raw opium causes catastrophic vascular blockages and severe infection.

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