麦角新碱

概览

Ergometrine is an ergot alkaloid used for the treatment of postpartum haemorrhage and post abortion hemorrhage in patients with uterine atony.

作用机制

Ergonovine directly stimulates the uterine muscle to increase force and frequency of contractions. With usual doses, these contractions precede periods of relaxation; with larger doses, basal uterine tone is elevated and these relaxation periods will be decreased. Contraction of the uterine wall around bleeding vessels at the placental site produces hemostasis. Ergonovine also induces cervical contractions. The sensitivity of the uterus to the oxytocic effect is much greater toward the end of pregnancy. The oxytocic actions of ergonovine are greater than its vascular effects. Ergonovine, like other ergot alkaloids, produces arterial vasoconstriction by stimulation of alpha-adrenergic and serotonin receptors and inhibition of endothelial-derived relaxation factor release. It is a less potent vasoconstrictor than ergotamine. As a diagnostic aid (coronary vasospasm), ergonovine causes vasoconstriction of coronary arteries.

适应症

Used to treat postpartum haemorrhage and postabortion haemorrhage in patients with uterine atony.

• Hemorrhage
• Vasospastic Angina