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Huxtable Ryan J.; Schwartz Stephen K. W. (2001). "The Isolation of Morphine—First Principles in Science and Ethics". Molecular Interventions. 1 (4): 189–191. PMID 14993340. Opioids can reduce the intensity and unpleasant feeling of pain. The unspecific effect of opium to the different opioid receptors produce the generation of various effects such as sedation, euphoria, dysphoria, respiratory depression, constipation, pruritus, nausea, and vomiting. It is reported that the secondary effects tend to be diminished as long-term use tolerance is developed. Some reports have also shown an opioid-driven impairment of the hypothalamic function that can result in a loss of libido, impotence, and infertility. Patients have reported a sensation of stress relief even in presence of pain as well as the presence of sedation, hypoventilation, cough inhibition, prolonged apnea, myosis and respiratory obstruction. 9 As a Class A drug the maximum sentence for the possession of opium is 7 years. The maximum sentences for supply and/or production are life imprisonment, a fine or both. History Michael-Titus A., Revest P. and Shortland P. (2010). The nervous system (2nd ed.). Churchill Livingstone.Liu HC, Ho HO, Liu RH, Yeh GC, Lin DL: Urinary excretion of morphine and codeine following the administration of single and multiple doses of opium preparations prescribed in Taiwan as "brown mixture". J Anal Toxicol. 2006 May;30(4):225-31. [ Article] Extensive textual and pictorial sources also show that poppy cultivation and opium consumption were widespread in Safavid Iran [42] and Mughal India. [43] England [ edit ]

Both analgesia and drug addiction are functions of the mu opioid receptor, the class of opioid receptor first identified as responsive to morphine. Tolerance is associated with the superactivation of the receptor, which may be affected by the degree of endocytosis caused by the opioid administered, and leads to a superactivation of cyclic AMP signaling. [152] Long-term use of morphine in palliative care and the management of chronic pain always entails a risk that the patient develops tolerance or physical dependence. There are many kinds of rehabilitation treatment, including pharmacologically based treatments with naltrexone, methadone, or ibogaine. [153] Sawynok J (January 1986). "The therapeutic use of heroin: a review of the pharmacological literature". Canadian Journal of Physiology and Pharmacology. 64 (1): 1–6. doi: 10.1139/y86-001. PMID 2420426. John Richards (May 23, 2001). "Opium and the British Indian Empire" . Retrieved September 24, 2007. Liang, Bin; Lu, Hong (2013). "Discourses of drug problems and drug control in China: Reports in the People's Daily, 1946–2009". China Information. 27 (3): 302. doi: 10.1177/0920203X13491387. S2CID 147627658.Drug Addiction Research and the Health of Women – pg. 33–52" (PDF). Archived from the original (PDF) on August 22, 2008 . Retrieved March 21, 2010. In the industrialized world, the United States is the world's biggest consumer of prescription opioids, with Italy being one of the lowest, because of tighter regulations on prescribing narcotics for pain relief. [143] Most opium imported into the United States is broken down into its alkaloid constituents, and whether legal or illegal, most current drug use occurs with processed derivatives such as heroin rather than with unrefined opium.