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Uterotonic (Ergot Alkaloid) Pregnancy: Contraindicated during pregnancy and during induction/first and second stage labour prior to delivery of the anterior shoulder (potent uterotonic activity). Ergometrine derivatives are excreted in breast milk (amounts unknown) and can suppress lactation - repeated use should be avoided.

Ergometrine

Brand names: Syntometrine (combined with oxytocin), Ergometrine Maleate

An ergot alkaloid uterotonic used in obstetrics to prevent and treat postpartum and post-abortal haemorrhage, often combined with oxytocin (as Syntometrine).

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 500 micrograms of ergometrine maleate IM (active management of the third stage of labour)
Route: Intramuscular (recommended); intravenous by slow injection in emergencies only
Frequency: Single dose (following delivery of the anterior shoulder or immediately after delivery)
Doses are expressed as ergometrine maleate (product: Ergometrine Injection BP 0.05% w/v). Active management of the third stage of labour: 500 micrograms IM (often combined with synthetic oxytocin 5 units) following delivery of the anterior shoulder or at the latest immediately after delivery of the baby. Prevention and treatment of postpartum haemorrhage: 200-500 micrograms IM following expulsion of the placenta or when bleeding occurs. In emergencies (severe haemorrhage due to uterine atony): 250-500 micrograms IV by slow injection only. Use under medical supervision only. Contraindicated in severe hepatic or renal impairment; caution in mild or moderate hepatic/renal impairment. Not for use before delivery is completed (contraindicated in pregnancy/labour prior to delivery of the anterior shoulder).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to the active substance or any excipient
  • Pregnancy and labour (induction, first and second stage prior to delivery of the anterior shoulder)
  • Primary or secondary uterine inertia
  • Severe hypertension, pre-eclampsia, eclampsia
  • Severe cardiac disorders; severe hepatic or renal impairment; occlusive vascular disease (e.g. Raynaud's); sepsis

Side effects

  • Nausea, vomiting, abdominal pain
  • Headache, dizziness
  • Hypertension, vasoconstriction
  • Cardiac arrhythmias, palpitations, bradycardia, chest pain, coronary arteriospasm (very rare myocardial infarction)
  • Dyspnoea, pulmonary oedema; anaphylactic/anaphylactoid reactions

Interactions

  • Strong CYP3A4 inhibitors (macrolides e.g. erythromycin, clarithromycin; HIV protease/reverse transcriptase inhibitors e.g. ritonavir; azole antifungals e.g. ketoconazole, itraconazole): avoid - risk of ergot toxicity (vasospasm, ischaemia)
  • Other vasoconstrictors / other ergot alkaloids: caution; concurrent vasoconstrictors after delivery during anaesthesia may cause severe postpartum hypertension
  • Triptans (5HT1B/1D agonists), sympathomimetics (including in local anaesthetics), beta-blockers: enhanced vasoconstrictor/vasopressor effect
  • Prostaglandins and their analogues: caution when used alone or in combination for postpartum atonic uterine haemorrhage

Clinical monograph

How it works

It directly stimulates uterine smooth muscle to produce sustained, tonic contraction, compressing uterine vessels and reducing bleeding.

Prescribing in practice

  • Contraindicated in pre-eclampsia, eclampsia, hypertension and significant cardiovascular disease because of the risk of severe vasoconstriction and dangerous blood-pressure rise.
  • Must not be given before delivery of the baby, and not for induction or augmentation of labour.
  • Use with caution alongside other vasoconstrictors and certain interacting drugs; nausea and vomiting are common after administration.

Monitoring

Monitor blood pressure and uterine tone (and ongoing blood loss) closely around administration.

Counselling the patient

  • Tell the team this is used to control bleeding after birth.
  • Nausea or vomiting may occur shortly after the injection.
  • Report severe headache, chest pain or breathlessness immediately.

Evidence & guidelines

Active management of the third stage of labour with a uterotonic is recommended by NICE to reduce postpartum haemorrhage.

Reference: RCOG Active Management of Third Stage of Labour; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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