mode of action

Last reviewed 01/2018

Myometrial action:

  • 500 mcg of ergometrine I.V. results in a uterine contraction within 40 sec which lasts 30 min

  • I.M. injection results in a contraction within 6 min

  • intrauterine injection may be employed if post-partum haemorrhage has resulted in peripheral shutdown

  • the combination of Syntocinon (5 U) with ergometrine (500 mcg) - called Syntometrine - is also used in the management of post-partum haemorrhage

If uterine tone is still inadequate, a SINGLE repeat dose of 500 mcg is permitted. No more than 1000 mcg may be given.

Vasoconstrictive action:

  • ergometrine may cause a dangerous increase in blood pressure in those who are already hypertensive