Carbetocin

Chemical structure of Carbetocin

Carbetocin is a synthetic oxytocin analogue used primarily in the prevention of postpartum hemorrhage (PPH) following cesarean section. It is a peptide and functions as a uterotonic, promoting uterine contractions to reduce bleeding after childbirth.

Mechanism of Action

Carbetocin acts on the oxytocin receptors in the myometrium, the smooth muscle layer of the uterus. By binding to these receptors, carbetocin stimulates uterine contractions, which help to compress the blood vessels and reduce blood loss. This action is similar to that of natural oxytocin, but carbetocin has a longer duration of action.

Clinical Use

Carbetocin is administered as a single intravenous or intramuscular injection immediately after the delivery of the baby during a cesarean section. Its use is particularly beneficial in settings where the risk of PPH is high, and it provides a longer-lasting effect compared to oxytocin, reducing the need for continuous infusion.

Pharmacokinetics

Carbetocin has a rapid onset of action, with uterine contractions occurring within minutes of administration. Its effects can last for several hours, which is advantageous in managing PPH. The drug is metabolized in the liver and excreted primarily in the urine.

Side Effects

Common side effects of carbetocin include nausea, vomiting, abdominal pain, and headache. In rare cases, it may cause hypotension or tachycardia. As with any medication, allergic reactions are possible, though they are uncommon.

Comparison with Oxytocin

While both carbetocin and oxytocin are used to prevent PPH, carbetocin offers the advantage of a longer duration of action, which can be particularly useful in resource-limited settings where continuous monitoring and infusion of oxytocin may not be feasible.

Related Pages

• Oxytocin
• Postpartum hemorrhage
• Cesarean section
• Uterotonic