Morphine (INN) (pronounced /ˈmɔrfiːn/) (MS Contin, MSIR, Avinza, Kadian, Oramorph, Roxanol) is a highly potent opiate analgesic psychoactive drug, is the principal active ingredient in Papaver somniferum (opium poppy, or simply opium), is considered to be the prototypical opioid. Like other opioids, e.g. oxycodone (OxyContin, Percocet, Percodan), hydromorphone (Dilaudid, Palladone), and diacetylmorphine (Heroin), morphine acts directly on the central nervous system (CNS) to relieve pain. Morphine has a high potential for addiction; tolerance and both physical and psychological dependence develop rapidly.

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