Morphine is the most abundant alkaloid found in opium, the dried sap (latex) derived from shallowly slicing the unripe seedpods of the opium, or common and/or edible, poppy, Papaver somniferum. Morphine was the first active principle purified from a plant source and is one of at least 50 alkaloids of several different types present in opium, poppy straw concentrate, and other poppy derivatives. Morphine is generally 8 to 14 percent of the dry weight of opium,[3] although specially bred cultivars reach 26 percent or produce little morphine at all, under 1 percent, perhaps down to 0.04 percent. The latter varieties, including the 'Przemko' and 'Norman' cultivars of the opium poppy, are used to produce two other alkaloids, thebaine and oripavine, which are used in the manufacture of semi-synthetic and synthetic opioids like oxycodone and etorphine and some other types of drugs. P. bracteatum does not contain morphine or codeine, or other narcotic phenanthrene-type, alkaloids. This species is rather a source of thebaine.[4] Occurrence of morphine in other papaverales and papaveraceae, as well as in some species of hops and mulberry trees has not been confirmed. Morphine is produced most predominantly early in the life cycle of the plant. Past the optimum point for extraction, various processes in the plant produce codeine, thebaine, and in some cases negligible amounts of hydromorphone, dihydromorphine, dihydrocodeine, tetrahydrothebaine, and hydrocodone (these compounds are rather synthesized from thebaine and oripavine). The human body produces endorphines, which are endogenous opioid peptides that function as neurotransmitters and have similar effects.[5]
In clinical medicine, morphine is regarded as the gold standard, or benchmark, of opioid analgesics used to relieve severe or agonizing pain and suffering. Like other opioids, such as oxycodone, hydromorphone, and diacetylmorphine (heroin), morphine acts directly on the central nervous system (CNS) to relieve pain. Morphine has a high potential for addiction; tolerance and psychological dependence develop rapidly, although physiological dependence may take several months to develop.
MS Contin is a brand of a time-released formulation of morphine sulfate, usually taken every twelve hours for chronic pain. MS Contin is a trademark of Purdue Pharma.
It is available in tablet and liquid formulas in doses of 15mg, 20mg, 30mg, 60mg, 100mg and 200mg. Due to its strength, it is typically prescribed to cancer patients and victims of severe but non-cognitive-damaging trauma.
MS Contin is a DEA Schedule II substance in the United States.
Alternative formulations made and marketed by other pharmaceutical companies include King Pharmaceuticals' Avinza and Actavis Pharmaceuticals' Kadian. Kadian is available in various strengths. There has been some concern[by whom?] regarding the issue that some capsules contain pellets (made by the process of extrusion and Spheronization (a trademark of Caleva Process Solutions) while others contain powder. There is no difference in efficacy between the powder and pellet forms.