Peptide LibraryAtosiban dosage in published studies and labels
These are the doses used for Atosiban in FDA labelling and published clinical studies, reported as each source states them, one row per regimen. They describe what was studied or approved for a specific population. They are not a recommendation, and none of them is a dose for any individual.
Research and educational reference only. This is not medical advice, and no figure on this page is a dosing recommendation.
Last checked against primary sources:
Studied regimens and sources
Atosiban has no FDA-approved dosage, but it is authorised in the European Union as Tractocile to delay imminent preterm birth at 24 to 33 completed weeks. The EU product information gives three intravenous steps: a 6.75 mg bolus over one minute, an infusion of 300 mcg a minute for 3 hours, then 100 mcg a minute for up to 45 hours, with treatment not exceeding 48 hours. The APOSTEL 8 trial found no improvement in newborn outcomes over placebo at 30 to 34 weeks.
Established Human Evidence
| Human dosing established | Yes |
|---|---|
| Route | Intravenous |
| Frequency | Bolus followed by continuous infusion |
| Duration studied | No more than 48 hours per course |
| Titration | Bolus 6.75 mg over 1 minute; loading infusion 300 mcg/minute (24 mL/hour) for 3 hours (54 mg); then 100 mcg/minute (8 mL/hour) for up to 45 hours (up to 270 mg). The EU product information says a full course should preferably not exceed 330.75 mg. |
| Half-life | Initial half-life about 0.21 hours and terminal half-life about 1.7 hours in women in preterm labour |
| Evidence level | Established Human Evidence |
| Last reviewed | 2026-11-07 |
Research-reported dosing
Doses as studied, one row per regimen. Different trials used different regimens; they are listed separately rather than averaged.
| Study / context | Population | Dose | Route | Frequency | Duration | Outcome studied | Source |
|---|---|---|---|---|---|---|---|
| EU product information — Tractocile, imminent preterm birth (EMA)Research-reported · EU regulatory product information (summary of product characteristics) | Pregnant adult women at 24 to 33 completed weeks with regular contractions, cervical dilation of 1–3 cm (0–3 cm in nulliparas), effacement of at least 50% and a normal fetal heart rate | 6.75 mg bolus, then 300 mcg/minute for 3 hours, then 100 mcg/minute for up to 45 hours | Intravenous | Bolus, then continuous infusion | Up to 48 hours; up to 3 re-treatments have limited clinical experience | Authorised in the EU to delay imminent preterm birth | Tractocile (atosiban) 6.75 mg/0.9 mL solution for injection — EU summary of product characteristics, EMA |
| Atosiban versus placebo in late threatened preterm birth — registry record (NCT05693688)Clinical trial · Randomised, double-blind, placebo-controlled phase 4 trial | Women 18 or older with a singleton or twin pregnancy and threatened preterm birth at 30+0 to 33+6 weeks (760 enrolled) | 6.75 mg bolus over one minute, then 18 mg/hour for 3 hours, then 6 mg/hour for the remaining 45 hours, or saline placebo | Intravenous | Bolus, then continuous infusion | 48 hours | Completed; no results are posted on ClinicalTrials.gov | NCT05693688 — Atosiban Versus Placebo in the Treatment of Late Threatened Pre-term Birth |
| APOSTEL 8 — Lancet 2025Clinical trial · Multicentre, randomised, double-blind superiority trial | Women aged 18 or older with a singleton or twin pregnancy and threatened preterm birth at 30+0 to 33+6 weeks (752 analysed) | Intravenous atosiban or placebo (regimen not stated in the indexed abstract) | Intravenous | Not stated in the indexed abstract | Not stated in the indexed abstract | Primary composite of perinatal death and severe newborn illness: 8% of infants with atosiban versus 9% with placebo (RR 0.90, 95% CI 0.58–1.40); superiority not shown | Atosiban versus placebo for threatened preterm birth (APOSTEL 8): a multicentre, randomised controlled trial. Lancet. 2025. |
| US placebo-controlled trial with tocolytic rescue (2000)Clinical trial · Multicentre, double-blind, placebo-controlled trial | Women in preterm labour (501 treated: 246 atosiban, 255 placebo) | Intravenous atosiban, then subcutaneous maintenance (amounts not stated in the indexed abstract) | Intravenous, then subcutaneous | Not stated in the indexed abstract | Not stated in the indexed abstract | No difference in time to delivery or treatment failure (primary endpoint; median 25.6 versus 21.0 days); more women stayed undelivered without another tocolytic at 24 hours, 48 hours and 7 days; fetal-infant deaths were higher with atosiban among those randomised before 24 weeks | An oxytocin receptor antagonist (atosiban) in the treatment of preterm labor: a randomized, double-blind, placebo-controlled trial with tocolytic rescue. Am J Obstet Gynecol. 2000. |
Where sources disagree
- Atosiban is an oxytocin receptor antagonist; the EU product information says treatment should be started and maintained by a physician experienced in treating preterm labour. The EU product information contraindicates it below 24 or after 33 completed weeks, with ruptured membranes after 30 weeks, abnormal fetal heart rate, bleeding needing immediate delivery, severe pre-eclampsia or eclampsia, fetal death, suspected infection, placenta praevia or abruption, and any other condition where continuing the pregnancy is hazardous.
- The FDA has not approved atosiban, and there is no atosiban label on DailyMed. The EU dosing row is marked as a regulatory document rather than a trial because the schema has no category for a non-US approval.