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See Morphine (band) for the rock band.

Molecular structure of morphine

CAS number
57-27-2 (anhydrous)
ATC code
Chemical formula C17H19NO3
Molecular weight 285.4
Bioavailability ~30%?
Metabolism renal 90%, biliary 10%
Elimination half-life 2-3 hours
Excretion renal
Pregnancy category Category C (Australia)
Legal status Schedule 8 (Australia),
Class A (UK),
Routes of administration oral, SC, IM

Morphine (INN), the principal active agent in opium, is a powerful opioid analgesic drug. According to recent research, it may also be produced naturally by the human brain.[1] Like other opiates, morphine acts directly on the central nervous system (CNS) to relieve pain, and at synapses of the arcuate nucleus, in particular. Side effects include impairment of mental performance, euphoria, drowsiness, lethargy, and blurred vision. It also decreases hunger, inhibits the cough reflex, and produces constipation. When not used as a treatment for pain, morphine is usually highly addictive, and tolerance and physical and psychological dependence develop quickly.

Morphine is frequently found in various preparations.

Parenterally (i.e. administered in a manner other than through the digestive tract), it is given as subcutaneous, intravenous, or epidural injections. The military sometimes issues morphine loaded in an autoinjector.

Orally, it comes as an elixir or in tablet form, though this is rare, as codeine is more effective orally. Morphine is rarely in suppository form.

Morphine is used legally in the following :

  • the relief of acute, severe pain
    • pain after surgery
    • pain associated with trauma
  • the relief of moderate to severe chronic pain
    • cancer pain
    • tooth extraction
  • as an adjunct to general anesthesia
  • in epidural anesthesia
  • relief of pain in palliative care (i.e. to alleviate pain without curing the underlying reason for it)

It was first isolated in 1803 by the German pharmacist Friedrich Wilhelm Adam Serturner, who named it 'morphium' after Morpheus, the Greek god of dreams. But it was not until the development of the hypodermic needle (1853) that its use spread. It was used for pain relief and, ironically, as a 'cure' for opium or alcohol addiction. Its extensive use during the American Civil War resulted in over 400,000 sufferers from the 'soldiers disease' (addiction).

Heroin was derived from morphine in 1874. Along with other drugs, its possession without a prescription was criminalised in the US by the Harrison Narcotics Tax Act of 1914.

Morphine is listed as a Class A drug under the 1971 Misuse of Drugs Act in the United Kingdom.


  • Acute pancreatitis

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