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Serturner, a pharmacist isolated the active principle of opium in 1806 and named it morphine. Morphine is a phenanthrene opioid receptor agonist, its main effect is binding to and activating the $\mu$-opioid receptors in the central nervous system. In clinical settings, morphine exerts its principal pharmacological effect on the central nervous system and gastrointestinal tract. Its primary actions of therapeutic value are analgesic and sedation.