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Medical Term:


Pronunciation: ok'se-to'sin


A nonapeptide neurohypophysial hormone, differing from human vasopressin in having a leucyl residue at position 8 and an isoleucyl residue at position 3, that causes myometrial contractions at term and promotes milk release during lactation; used to induce or stimulate labor, to manage postpartum hemorrhage and atony, and to relieve painful breast engorgement.

Synonym(s): ocytocin

[G. okytokos, swift birth]

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