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Medical Term:


Pronunciation: mor'fen, mor-fen'


The major phenanthrene alkaloid of opium; it produces a combination of depression and excitation in the central nervous system and some peripheral tissues; predominance of either central stimulation or depression depends on the species and dose; repeated administration leads to the development of tolerance, physical dependence, and (if abused) psychic dependence. Used as an analgesic, sedative, and anxiolytic.

[L. Morpheus, god of dreams or of sleep]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.