Ergometrine: Formula, Indications, Mechanism of Action, Dosage, Side Effects, Warnings, Contraindications and Interactions

It is a type of medicine called an ergot alkaloid.

It is used to help prevent and control bleeding after childbirth. The active ingredient belongs to a group of drugs known as ergot alkaloids.

These medications are responsible for stopping the excessive bleeding that sometimes occurs after abortion or after the baby is born, causing the uterus muscle to contract.

Ergometrine is prescribed for postpartum and uterine bleeding and the management of the third stage of labor.

Chemical formula

  • C19H23N3O2.


  • In 0.2 mg tablets by mouth.
  • In the injectable solution of 0.2 mg per ml.
  • Also, powder composition.


Ergometrine injection is used for uterine atony, uterine bleeding, subinvolution of the uterus, and other conditions.

When used in the active management of the third stage of labor, the injection is given at delivery or immediately after delivery.

This helps release the placenta and reduce the risk of heavy bleeding after the placenta disappears.


Mechanism of action of ergometrine

Ergometrine acts on the muscles of the uterus, increasing rhythmic contractions.

Ergometrine acts on three different types of receptors found on the walls of blood vessels and in the uterus.

When ergometrine stimulates these receptors, the blood vessels constrict and, consequently, the uterus. Contractions help push out the placenta.

Both of these actions reduce blood flow to the uterus, which helps lower blood loss as the placenta exits the wall of the uterus.


The ergometrine dose that your doctor recommends will be based primarily on the following:

  • The condition is being treated.
  • The patient suffered other medical conditions.
  • The medications you are taking.
  • The answer to this drug.
  • The weight.
  • The height.
  • Age.
  • The gender.

Generally, the doses that are managed for pregnant women are the following:


  1. Oral route: 0.2 to 0.4 mg, 2 or 4 times a day. Maximum duration: 1 week after delivery.
  2. Intravenous route: for excessive uterine bleeding, administer 200 mcg for at least 1 minute, followed by oral doses of 0.2 or 0.4 mg, 2 to 4 times a day.

Ergometrine Side Effects

Side effects that may occur with the administration of ergometrine are:

  • Hypertension.
  • Abdominal pain
  • Nausea
  • Vomiting
  • The myocardial infarction.
  • Pain in the chest.
  • Vasoconstriction.
  • Vasospasm.
  • Coronary artery spasm.
  • Bradycardia

Warnings and Contraindications

Before using ergometrine, the doctor should be informed of the current list of medications, including over-the-counter products (e.g., vitamins, herbal supplements, etc.).

It should be reported if the patient suffers from allergies, especially if they have an allergy to the drug. Also, the list of pre-existing diseases and current health conditions, as some health conditions can make the patient more susceptible to the side effects of ergometrine.

This medicine should be taken as prescribed by the doctor or follow the directions on the printed package insert of the product.

The dose is based on the condition of each patient.

If the condition persists or worsens, a doctor should be consulted.

This medicine should not be used if:

  • An abnormal fetal presentation is known to exist.
  • The patient is chronically anemic.
  • These are newborns.
  • The patient has liver, kidney, respiratory, or heart failure.
  • The patient is hypertensive.
  • There is hypocalcemia.
  • The woman is breastfeeding.
  • In the 1st and 2nd stages of labor.
  • In cases of porphyria.
  • The patient has pre-eclampsia or eclampsia.
  • There is a threat of miscarriage.

Blood pressure, pulse, and uterine response should be monitored during administration.

Routine intravenous administration can cause sudden strokes and high blood pressure.

Ergometrine interactions

If the patient takes other medications together with ergometrine, the effects could change, which is why in some cases, it could increase the risk of side effects and in others by modifying the results of the medications.

Ergometrine has been reported to interact with the following medications and products:

  • The adrenaline.
  • Ephedrine
  • Erythromycin.
  • Halothane.
  • Ketamine.
  • La mifepristone.
  • Oxprenolol.
  • Oxytocin.