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Medical Term:

slow-reacting substance


a lipoprotein of low molecular weight composed of leukotrienes; it is released in anaphylactic shock and produces slower and more prolonged contraction of muscle than histamine does; it is active in the presence of antihistamines (but not epinephrine) and is newly generated after unpreformed mast cell generation; it induces the effect observed in anaphylactic reactions.

Synonym(s): slow-reacting factor of anaphylaxis

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