Carbetocin
A long-acting oxytocin analogue given once after birth: heat-stable carbetocin matched oxytocin in a 29,645-woman trial, and WHO now recommends carbetocin for preventing postpartum haemorrhage
Carbetocin is a synthetic analogue of oxytocin, the hormone that contracts the uterus after birth. A single injection after delivery helps prevent the uterine atony behind most postpartum haemorrhage, and it acts longer than oxytocin, with an elimination half-life of about 41 to 43 minutes in healthy women. A heat-stable formulation needs no refrigeration, and in WHO's CHAMPION trial of 29,645 women it was non-inferior to oxytocin after vaginal birth. It is authorised in the UK and elsewhere but has never been approved in the US.
What is it?
Postpartum haemorrhage is the most common cause of maternal death. Oxytocin is the standard drug for preventing it, but it needs cold storage that many countries cannot provide, and heat degrades it. Carbetocin is a synthetic analogue of oxytocin with a modified ring and a methylated tyrosine. In a pharmacokinetic study in 25 healthy nonpregnant women its elimination half-life after intravenous doses was 41 to 43 minutes, it reached the circulation within 30 minutes of an intramuscular injection with about 80% bioavailability, and under 1% left unchanged in the urine.
The decisive trial was WHO's CHAMPION. At 23 sites in 10 countries, 29,645 women were randomised after vaginal birth to an intramuscular injection of heat-stable carbetocin 100 µg or oxytocin 10 IU, both kept cold to preserve blinding. Blood loss of at least 500 ml or the need for another uterotonic occurred in 14.5% against 14.4% (relative risk 1.01), meeting the non-inferiority margin; for blood loss of at least 1,000 ml (1.51% against 1.45%) non-inferiority was not shown, a result the investigators attributed to low event rates. A meta-analysis of five trials in 30,314 women after vaginal delivery found no significant difference from oxytocin.
At caesarean section the evidence leans its way. A Bayesian meta-analysis of 30 trials found that carbetocin reduced the need for additional uterotonics after caesarean (relative risk 0.43) and in high-risk vaginal births (0.56), with fewer transfusions (0.57). At elective caesarean, a 20 µg dose gave uterine tone non-inferior to 100 µg.
The UK label authorises one 100 µg dose after delivery, intravenously at caesarean and intravenously or intramuscularly after vaginal birth. WHO added heat-stable carbetocin to its Model List of Essential Medicines in 2019, and its 2025 postpartum haemorrhage guideline recommends carbetocin for all births and heat-stable carbetocin where the oxytocin cold chain cannot be maintained. Cost has limited its use: the Scottish Medicines Consortium did not recommend Pabal for NHS Scotland in 2017. It has never been approved in the US. Separately, an intranasal formulation was tested in Prader-Willi syndrome.
Mechanism of Action
Carbetocin works through the same receptor as oxytocin. Its changed structure lets one dose do the job that oxytocin usually needs an infusion for.
Oxytocin receptor agonist
It activates the oxytocin receptor on uterine muscle, producing the sustained contraction that closes the blood vessels at the placental site after delivery; uterine tone was comparable to oxytocin's at 2, 5 and 10 minutes in a four-arm caesarean trial.
A longer-lasting structure
Replacing oxytocin's disulfide with a thioether ring and methylating tyrosine give an elimination half-life of about 41 to 43 minutes after intravenous doses, with a distribution half-life of 5.5 to 6.1 minutes and mainly non-renal elimination.
Heat stability
The heat-stable formulation used in CHAMPION removes the need for the cold chain that oxytocin depends on; heat degradation is one of the main reasons oxytocin loses effectiveness where refrigeration fails.
One dose, two routes
Given intramuscularly it reaches the circulation within 30 minutes with about 80% bioavailability; the UK label allows intravenous or intramuscular use after vaginal birth and intravenous use at caesarean.
Published Research
These are the studies behind carbetocin, read from their PubMed abstracts: WHO's CHAMPION trial and a nested study, meta-analyses after vaginal and caesarean birth, caesarean trials, the Prader-Willi trial and a veterinary pharmacokinetic study.
CHAMPION: 29,645 women after vaginal birth
At 23 sites in 10 countries, intramuscular heat-stable carbetocin 100 µg was compared with oxytocin 10 IU, both refrigerated to keep blinding. Blood loss of at least 500 ml or an additional uterotonic occurred in 14.5% against 14.4% (relative risk 1.01, 95% CI 0.95 to 1.06), non-inferior; blood loss of at least 1,000 ml was 1.51% against 1.45% (1.04, 0.87 to 1.25), where non-inferiority was not shown. Other uterotonics, interventions and adverse effects did not differ.
CHAMPION's nested haemoglobin study in India
Among 1,799 women at one CHAMPION site in southern India, blood loss did not differ, but haemoglobin 48 to 72 hours after delivery was slightly lower after carbetocin than after oxytocin (10.09 against 10.21 g/dL, P=0.043).
Meta-analysis after vaginal delivery: 30,314 women
Across five randomised trials, blood loss of at least 500 ml did not differ significantly between carbetocin and oxytocin (relative risk 0.52, 95% CI 0.24 to 1.15), nor did blood loss of 1,000 ml, additional uterotonics, transfusion or side effects; the authors concluded that the choice will depend on cost-effectiveness.
Bayesian meta-analysis of 30 trials
Compared with oxytocin, carbetocin reduced the need for additional uterotonics after caesarean (relative risk 0.43, 95% CI 0.30 to 0.59; 3,216 women) and in high-risk vaginal births (0.56, 0.34 to 0.94; 789 women), and reduced postpartum transfusion (0.57, 0.33 to 0.96; 1,991 women).
Low and standard doses at elective caesarean
In 277 low-risk patients under spinal anaesthesia, carbetocin 20 µg gave uterine tone of 8 at two minutes, non-inferior to 8 with carbetocin 100 µg (difference 0); low-dose oxytocin was likewise non-inferior to standard dose, and later tone, additional uterotonics, blood loss and adverse effects were similar across the four groups.
Intranasal carbetocin in Prader-Willi syndrome
In a phase 3 trial of 130 participants aged 7 to 18, stopped early by the COVID-19 pandemic, neither primary endpoint (hyperphagia and obsessive-compulsive scores at 9.6 mg) reached significance; the 3.2 mg dose showed nominally significant improvements in hyperphagia, anxiety and distress and global impression, sustained over follow-up. Mild to moderate flushing was the commonest adverse event.
Where the research stood in 2018
Searching trial registries and Cochrane reviews, the authors described ongoing trials large enough to change guidelines, and noted that heat degradation is one of the key causes of oxytocin's reduced effectiveness in preventing haemorrhage from uterine atony.
Pharmacokinetics in cows and gilts
After single intravenous or intramuscular doses, carbetocin was absorbed and eliminated quickly in both species, with a longest terminal half-life of 0.85 hours. Intramuscular peak concentrations were about half the intravenous ones, and bioavailability exceeded 80% in cows.
Dosing Data
Carbetocin is given once, by clinical staff, right after the baby is delivered. The UK label sets the dose.
Educational information, not medical advice. Each dose above is tagged with its source: an approved label, a published human study, animal data, or amounts reported by users. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose. Full medical disclaimer.
Side Effects & Contraindications
Reported Side Effects
From the trials above.
Contraindications & Cautions
From the label and trials; the obstetric team decides.
Legal Status
Carbetocin is authorised in the UK and other countries and not approved in the US.
Frequently Asked Questions
?What is carbetocin used for?
Preventing heavy bleeding after childbirth caused by the uterus failing to contract. One 100 µg injection is given right after the baby is delivered.
?Is carbetocin better than oxytocin?
After vaginal birth it was non-inferior to oxytocin in CHAMPION, a trial of 29,645 women. After caesarean, a meta-analysis found it reduced the need for extra uterotonic drugs (relative risk 0.43). Its main practical advantage is that the heat-stable form needs no refrigeration.
?Is carbetocin approved in the US?
No. FDA's Drugs@FDA database holds no application for it. It is authorised in the UK as Pabal and sold by Ferring under other names elsewhere.
?What does WHO recommend?
WHO's 2025 postpartum haemorrhage guideline recommends carbetocin for all births, and heat-stable carbetocin where the oxytocin cold chain cannot be maintained. Heat-stable carbetocin has been on WHO's essential medicines list since 2019.
?How long does it last?
Its elimination half-life after intravenous doses was about 41 to 43 minutes in healthy women, and an intramuscular dose was about 80% bioavailable.
?Why is it on a peptide site?
It is a synthetic peptide analogue of oxytocin, and it belongs beside oxytocin and vasopressin in our encyclopedia. It is a hospital obstetric medicine with no other use.
References
- [fda-pi] Ferring Pharmaceuticals. PABAL 100 micrograms/ml solution for injection, Summary of Product Characteristics, sections 4.1-4.2 (prevention of postpartum haemorrhage due to uterine atony; 100 µg once, IV at caesarean, IV or IM after vaginal delivery). EMC, last updated August 6, 2025; read September 30, 2026.
- [clinical-trial] Pharmacokinetics of carbetocin, a long-acting oxytocin analogue, in nonpregnant women (25 healthy women; elimination half-life 41 and 42.7 minutes after 0.4 and 0.8 mg IV; IM bioavailability about 80%). Not PubMed-indexed; English summary read in Lund University's publication record, September 30, 2026.
- [pubmed] Widmer M, et al. "Heat-Stable Carbetocin versus Oxytocin to Prevent Hemorrhage after Vaginal Birth." N Engl J Med, 2018;379(8):743-752. PMID: 29949473.
- [pubmed] Vernekar SS, et al. "Effect of heat stable carbetocin vs oxytocin for preventing postpartum haemorrhage on post delivery hemoglobin-a randomized controlled trial." J Matern Fetal Neonatal Med, 2022;35(25):8744-8751. PMID: 34763599.
- [pubmed] Jin XH, et al. "Carbetocin vs oxytocin for prevention of postpartum hemorrhage after vaginal delivery: A meta-analysis." Medicine (Baltimore), 2019;98(47):e17911. PMID: 31764790.
- [pubmed] Kalafat E, et al. "Efficacy of carbetocin in the prevention of postpartum hemorrhage: a systematic review and Bayesian meta-analysis of randomized trials." J Matern Fetal Neonatal Med, 2021;34(14):2303-2316. PMID: 31537134.
- [pubmed] McDonagh F, et al. "Carbetocin vs. oxytocin at elective caesarean delivery: a double-blind, randomised, controlled, non-inferiority trial of low- and high-dose regimens." Anaesthesia, 2022;77(8):892-900. PMID: 35343585.
- [pubmed] Roof E, et al. "Intranasal Carbetocin Reduces Hyperphagia, Anxiousness, and Distress in Prader-Willi Syndrome: CARE-PWS Phase 3 Trial." J Clin Endocrinol Metab, 2023;108(7):1696-1708. PMID: 36633570.
- [pubmed] Theunissen FJ, et al. "Current research on carbetocin and implications for prevention of postpartum haemorrhage." Reprod Health, 2018;15(Suppl 1):94. PMID: 29945640.
- [pubmed] Sun P, et al. "Pharmacokinetics and bioavailability of carbetocin after intravenous and intramuscular administration in cows and gilts." J Vet Pharmacol Ther, 2020;43(2):237-240. PMID: 31856330.
- [guideline] World Health Organization (2025). Consolidated guidelines for the prevention, diagnosis and treatment of postpartum haemorrhage: carbetocin 100 µg IM/IV recommended for all births; heat-stable carbetocin where the oxytocin cold chain cannot be maintained. Recommendations read in the PAHO/BVS BIGG-rec database, September 30, 2026.
- [other] World Health Organization. Model List of Essential Medicines: carbetocin (heat stable), 100 µg/mL injection, core list, first added in 2019 (TRS 1021). Read at list.essentialmeds.org, September 30, 2026.
- [other] Scottish Medicines Consortium. Carbetocin 100 micrograms/mL solution for injection (Pabal), SMC No 309/06: not recommended for use within NHS Scotland (advice of December 8, 2017, published January 15, 2018).
- [fda] FDA. Drugs@FDA (openFDA): no application for carbetocin. Read September 30, 2026.
Sources & Citations
Every study on this page was read from its PubMed record. The half-life comes from the published pharmacokinetic study in 25 women, the dose from the UK label, and regulatory status from Drugs@FDA, WHO and the Scottish Medicines Consortium, read September 30, 2026. Grey Peptides sells nothing and links to no vendor.
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