Version July 2025
Elective induction of labor is defined as the initiation of labor in a pregnant individual who has no medical indications for induction. Since the available data are inadequate to evaluate the benefits-to-risks considerations, oxytocin is not indicated for elective induction of labor.
Labor induction or augmentation: Note: To minimize medication errors, administration of the dose using a standardized concentration and infusion protocol is recommended (Ref). Administration requires continuous fetal and uterine monitoring. The ideal dosing regimen has not been established and various protocols are available (Ref); examples of regimens are listed below. Refer to institution-specific protocol.
Low-dose regimen (off-label dose): IV: Initial: 0.5 to 2 milliunits/minute; incrementally increase by 1 to 2 milliunits/minute every 15 to 40 minutes as needed according to response (eg, contractions and fetal heart rate) (Ref). Reduce dose or discontinue in the event of uterine tachysystole and/or fetal distress. See "Dose adjustment for oxytocin-induced uterine tachysystole."
High-dose regimen (off-label dose): IV: Initial: 4 to 6 milliunits/minute; incrementally increase by 3 to 6 milliunits/minute every 15 to 40 minutes as needed according to response (eg, contractions and fetal heart rate) (Ref). Reduce dose or discontinue in the event of uterine tachysystole and/or fetal distress. See "Dose adjustment for oxytocin-induced uterine tachysystole."
Maximum dose: Not clearly established. Many protocols suggest a maximum dose of 40 milliunits/minute; however, higher doses (eg, 90 milliunits/minute) have been used (Ref). In patients with prior cesarean birth, lower maximum doses (eg, 20 milliunits/minute) may be preferred (Ref).
Dose adjustment for oxytocin-induced uterine tachysystole:
Normal fetal heart rate: Reduce the dose (eg, decrease oxytocin infusion rate by 50%) or discontinue oxytocin until tachysystole resolves (Ref). Practice varies and depends on multiple factors (eg, frequency of contractions, dose of oxytocin when tachysystole occurred).
Indeterminate or abnormal fetal heart rate: Discontinue oxytocin and initiate other measures (eg, maternal repositioning, administration of IV fluids) (Ref). Prompt administration of another agent (eg, terbutaline) may be needed if fetal heart rate (FHR) changes are concerning for acidemia (Ref).
Restarting infusion: Following resolution of uterine tachysystole when contraction frequency, intensity, and duration and FHR are normal, oxytocin may be restarted (eg, if discontinued for <30 minutes, restart oxytocin at no more than 50% of the rate that caused the tachysystole and gradually adjust dose based on protocol and maternal/fetal status; if discontinued for >30 minutes, restart at the initial infusion rate) (Ref).
Discontinuation of therapy in the active phase of labor: May continue infusion through delivery or discontinue infusion once cervical dilation is 5 to 6 cm and adequate contractions (Ref). Note: If discontinued, oxytocin is typically restarted after delivery of the placenta, delivery of the anterior shoulder, or after delayed umbilical cord clamping for prevention of postpartum uterine hemorrhage (Ref). Refer to "Postpartum uterine hemorrhage."
Postpartum uterine hemorrhage: Note: To minimize medication errors, administration of the dose using a standardized concentration and infusion protocol is recommended (Ref). The optimal IV regimen has not been established (Ref); examples of regimens are listed below. Refer to institution-specific protocol.
Prevention of postpartum hemorrhage: Note: Administer oxytocin after delivery of the placenta, delivery of the anterior shoulder, or after delayed umbilical cord clamping (Ref). In patients at high risk for hemorrhage, a second medication (eg, tranexamic acid, misoprostol) may be used; some experts use combination therapy in all patients regardless of hemorrhage risk (Ref).
IV: 10 units over 30 minutes, then decrease rate to 7.5 units/hour. Alternatively, may administer 1 to 3 units as a slow IV bolus followed by a maintenance infusion of up to 7.5 units/hour (Ref). Adjust infusion rate to sustain uterine contraction and control uterine atony, and then decrease rate (eg, to 1 to 2.5 units/hour) if uterine tone is maintained and bleeding is not excessive (Ref). Usual duration is 2 to 4 hours, but longer durations (up to 8 hours) may be used in patients at high risk for hemorrhage (Ref). If previously administered during labor, larger infusion doses may be necessary (Ref).
IM: 10 units given once (Ref).
Treatment of postpartum hemorrhage: Note: Prompt administration of uterotonic medication(s) for postpartum hemorrhage (an obstetric emergency) is required; if hemorrhage is not controlled by medications, minimally invasive measures and/or emergency invasive intervention may also be warranted. The optimal IV regimen has not been established; an example regimen is listed below. Refer to institution-specific protocol.
IV: 30 to 40 units/hour for 10 to 15 minutes to control uterine atony, followed by a continuous lower rate to maintain uterine contractions (Ref). If already administered IV for preventive therapy (most patients), may increase infusion rate (Ref). If previously administered during labor, larger infusion doses may be necessary (Ref).
IM: 10 units given once in conjunction with other interventions (Ref). Note: If already administered IM for preventative therapy, treatment is typically not repeated (given the long duration of action with IM use). Intramyometrial administration may also be used (Ref).
Maximum dose: Not clearly established; some guidelines recommend a maximum cumulative dose of 40 units for both prevention and treatment (Ref). Some data suggest a greater risk of cardiovascular adverse effects with high doses over a shorter period of time or rapid IV boluses than with higher cumulative doses over a longer period of time (Ref).
Pregnancy termination, second trimester medication abortion (alternative agent) (off-label use): Note: Alternative if misoprostol is not available.
IV: Initial: 20 to 100 units over 3 hours, then stop the infusion for 1 hour to allow for diuresis. Restart the infusion by slowly increasing the rate at 3-hour intervals (eg, by 50 units every 3 hours) until fetal expulsion occurs; maximum rate: 300 units over 3 hours (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no dosage adjustments provided in the manufacturer's labeling.
There are no dosage adjustments provided in the manufacturer's labeling.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.
Frequency not defined:
Cardiovascular: Cardiac arrhythmia, hypertensive crisis, hypotension (Dyer 2011), subarachnoid hemorrhage, tachycardia (Dyer 2011), ventricular premature contractions
Endocrine & metabolic: Water intoxication (severe water intoxication with seizure and coma is associated with a slow oxytocin infusion over 24 hours)
Gastrointestinal: Nausea, vomiting
Genitourinary: Postpartum hemorrhage, uterine rupture
Hematologic & oncologic: Pelvic hematoma
Hypersensitivity: Anaphylaxis
Hypersensitivity to oxytocin or any component of the formulation; significant cephalopelvic disproportion; unfavorable fetal positions or presentations (such as transverse lies); fetal distress when delivery is not imminent; hypertonic or hyperactive uterus; contraindicated vaginal delivery (invasive cervical cancer, active genital herpes, prolapse of the cord, cord presentation, total placenta previa, or vasa previa); obstetrical emergencies where surgical intervention is favored; where adequate uterine activity fails to achieve satisfactory progress.
Canadian labeling: Additional contraindications (not in the US labeling): Severe toxemia; prematurity or unripe cervix; predisposition to uterine rupture (eg, grand multiparity, overdistention of the uterus, previous caesarian delivery, other surgery involving the uterus); prolonged use in uterine inertia; factors predisposing to thromboplastin or amniotic fluid embolism (eg, prolonged retention of dead fetus, placental abruption); serious medical or obstetric conditions and any condition in which fetal distress already occurs; inability of physician to be in attendance
Concerns related to adverse effects:
• Antidiuretic effect: Oxytocin may produce intrinsic antidiuretic effect (ie, water intoxication). Severe water intoxication with convulsions, coma, and death may occur, particularly with large doses (40 to 50 milliunits/minute) administered as a slow infusion over 24 hours and if the patient is receiving additional fluids.
• Cardiovascular effects: Arrhythmias, hypotension, myocardial ischemia, peripheral vasodilation, and tachycardia have been reported following administration. The risk of adverse events is influenced by dose and route of administration and is increased in patients with cardiovascular disease. Use with extreme caution in hemodynamically unstable patients (Dyer 2011).
• Maternal deaths: Maternal deaths caused by hypertensive episodes, subarachnoid hemorrhage, or rupture of the uterus and fetal deaths have occurred with oxytocic medications when used for induction of labor or for augmentation in the first and second stages of labor.
• Uterine effects: High doses or hypersensitivity to oxytocin may cause uterine hypertonicity, spasm, tetanic contraction, or rupture of the uterus. Prolonged infusion of oxytocin may saturate uterine receptors, causing inadequate uterine contractions and prolonged labor (AWHONN [Simpson 2020], Vallera 2017).
Other warnings/precautions:
• Appropriate use: Labor induction: Oxytocin is used to initiate or improve uterine contractions in order to replicate spontaneous labor and achieve a vaginal delivery. Use for induction of labor is generally not recommended in the following conditions: Fetal distress, hydramnios, partial placenta previa, prematurity, borderline cephalopelvic disproportion, or conditions where there is a predisposition for uterine rupture (eg, previous major surgery on cervix or uterus, cesarean section, overdistention of the uterus, grand multiparity, past history of uterine sepsis or traumatic delivery).
• Trained personnel: IV preparations should be administered by adequately trained individuals familiar with its use and able to identify complications; continuous observation is necessary for all patients. The use of one standardized concentration for the induction or augmentation of labor and the management of postpartum uterine bleeding is recommended to minimize errors (AWHONN 2021; AWHONN [Simpson 2020]; ISMP [Smetzer 2022]). Administration of ready-to-use bags boldly labeled on both sides (to differentiate from other solutions), not bringing the prepared oxytocin infusion to the patient's bedside until needed, and the use of standardized order sets are additional best practice safety interventions (ISMP [Smetzer 2022]).
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Solution, Injection:
Pitocin: 10 units/mL (1 mL, 10 mL, 50 mL) [contains chlorobutanol (chlorobutol)]
Generic: 10 units/mL (1 mL, 10 mL, 30 mL)
Yes
Solution (Oxytocin Injection)
10 units/mL (per mL): $1.80 - $4.14
Solution (Pitocin Injection)
10 units/mL (per mL): $1.68
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Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Solution, Injection:
Generic: 10 units/mL (1 mL, 5 mL, 10 mL)
The use of one standardized concentration and administration protocol (eg, the rate and interval for dose increases) for the induction or augmentation of labor and the management of postpartum uterine bleeding is recommended to minimize errors (Ref). Administration of ready-to-use bags boldly labeled on both sides (to differentiate from other solutions), not bringing the prepared oxytocin infusion to the patient's bedside until needed, and the use of standardized order sets are additional best practice safety interventions (Ref).
Labor induction or augmentation: IV administration requires the use of an infusion pump that allows minute-to-minute adjustments; refer to indication-specific infusion rates in dosing for detailed recommendations. The oxytocin solution can be piggybacked to an isotonic electrolyte infusion line proximal to the venipuncture site (Ref).
Postpartum uterine hemorrhage: Administer by IV or IM. IM administration may be used when IV access is not available (Ref). IV push is not recommended; rapid IV bolus administration is associated with cardiovascular collapse (Ref). Slow IV injections (5 or 10 units over 1 minute) are preferred for patients without cardiovascular risk factors; very slow injections (>5 minutes) are preferred for patients with cardiovascular risk factors (Ref); refer to indication-specific infusion rates in dosing for detailed recommendations. Administration IV is preferred over IM injection for the prevention of postpartum hemorrhage following vaginal delivery in patients who already have IV access (Ref). Either route of administration may be used in patients undergoing cesarean delivery (Ref).
Pregnancy termination: Administer by IV infusion; refer to indication-specific infusion rates in dosing for detailed recommendations.
Hazardous agent (NIOSH 2024 [table 2]).
Use appropriate precautions for receiving, handling, storage, preparation, dispensing, transporting, administration, and disposal. Follow NIOSH and USP 800 recommendations and institution-specific policies/procedures for appropriate containment strategy (NIOSH 2023; NIOSH 2024; USP-NF 2020).
Note: Facilities may perform risk assessment of some hazardous drugs to determine if appropriate for alternative handling and containment strategies (USP-NF 2020). Refer to institution-specific handling policies/procedures.
Labor induction or augmentation: Antepartum use for the initiation or improvement of uterine contractions, where this is desirable and considered suitable for reasons of fetal or maternal concern, in order to achieve vaginal delivery. Induction of labor in patients with a medical indication (eg, Rh problems [isoimmunization], maternal diabetes, preeclampsia, at or near term) when delivery is in the best interests of mother and fetus or when membranes are prematurely ruptured, and delivery is indicated; stimulation or reinforcement of labor (as in selected cases of uterine inertia).
Note: Oxytocin may also be used for other medical conditions in antepartum labor induction, including chronic or gestational hypertension, fetal compromise (eg, severe fetal growth restriction or oligohydramnios), or augmentation of labor, used when contractions are inadequate to produce a cervical change in dilation and effacement (ACOG 2009; AWHONN [Simpson 2020]).
Postpartum uterine hemorrhage: To produce uterine contractions during the third stage of labor and to control postpartum hemorrhage.
Pregnancy termination, second trimester medication abortion:
Limitations of use: Oxytocin monotherapy may be used as an alternative to misoprostol for second trimester medication abortion if misoprostol is not available (ACOG 2013; Zwerling 2023). Note: Dosing in the prescribing information for the adjunctive treatment of abortion may not reflect current clinical practice; other therapy may be required.
Labor induction, elective
The Institute for Safe Medication Practices (ISMP) includes this medication among its list of drugs which have a heightened risk of causing significant patient harm when used in error (High-Alert Medications in Acute Care Settings).
Oxytocin may be confused with OxyCONTIN
Pitocin may be confused with PIT or Pitressin (names to describe vasopressin), pitolisant
OXY is an error-prone abbreviation (mistaken as oxyCODONE, OxyCONTIN)
PIT is an error-prone abbreviation for Pitocin (mistaken as Pitressin [a discontinued brand of vasopressin still referred to as PIT])
None known.
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
Amisulpride (Oral): May increase QTc-prolonging effects of QT-prolonging Agents (Moderate Risk). Risk C: Monitor
Azithromycin (Systemic): QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Azithromycin (Systemic). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Carbetocin: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Carbetocin. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Carboprost Tromethamine: May increase adverse/toxic effects of Oxytocic Agents. Specifically, oxytocic effects may be enhanced. Risk X: Avoid
Chloroquine: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Chloroquine. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Clofazimine: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Clofazimine. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Dabrafenib: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Dabrafenib. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Dinoprostone: May increase adverse/toxic effects of Oxytocin. Specifically, oxytocic effects may be enhanced. Management: Concomitant use of dinoprostone and oxytocin is not recommended. If used sequentially, monitor uterine activity closely. Administer oxytocin 30 minutes after removing dinoprostone vaginal insert and 6 to 12 hours after the application of dinoprostone gel. Risk D: Consider Therapy Modification
Domperidone: QT-prolonging Agents (Moderate Risk) may increase QTc-prolonging effects of Domperidone. Risk X: Avoid
Encorafenib: May increase QTc-prolonging effects of QT-prolonging Miscellaneous Agents (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
EPHEDrine (Nasal): Oxytocin may increase hypertensive effects of EPHEDrine (Nasal). Risk C: Monitor
EPHEDrine (Systemic): Oxytocin may increase hypertensive effects of EPHEDrine (Systemic). Risk C: Monitor
Fexinidazole: May increase QTc-prolonging effects of QT-prolonging Miscellaneous Agents (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Fluorouracil Products: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Fluorouracil Products. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Gadobenate Dimeglumine: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Gadobenate Dimeglumine. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Gemeprost: May increase adverse/toxic effects of Oxytocin. Risk X: Avoid
Halofantrine: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Halofantrine. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Haloperidol: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Haloperidol. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Inotuzumab Ozogamicin: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Inotuzumab Ozogamicin. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Levoketoconazole: QT-prolonging Agents (Moderate Risk) may increase QTc-prolonging effects of Levoketoconazole. Risk X: Avoid
Lofexidine: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Lofexidine. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Midostaurin: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Midostaurin. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
MiSOPROStol: May increase adverse/toxic effects of Oxytocic Agents. Specifically, the oxytocic effects may be increased. Management: The concomitant use of misoprostol with other oxytocic agents is not recommended. If sequential use of oxytocin is necessary, oxytocin should be given at least 4 hours after misoprostol. Risk X: Avoid
Ondansetron: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Ondansetron. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Pentamidine (Systemic): QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Pentamidine (Systemic). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Pimozide: May increase QTc-prolonging effects of QT-prolonging Agents (Moderate Risk). Risk X: Avoid
Piperaquine: QT-prolonging Agents (Moderate Risk) may increase QTc-prolonging effects of Piperaquine. Risk X: Avoid
Probucol: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Probucol. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QT-prolonging Agents (Highest Risk): Oxytocin may increase QTc-prolonging effects of QT-prolonging Agents (Highest Risk). Management: Consider alternatives to this drug combination. If combined, monitor for QTc interval prolongation and ventricular arrhythmias. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk D: Consider Therapy Modification
QT-prolonging Antidepressants (Moderate Risk): May increase QTc-prolonging effects of QT-prolonging Miscellaneous Agents (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QT-prolonging Antipsychotics (Moderate Risk): QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of QT-prolonging Antipsychotics (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QT-prolonging Class IC Antiarrhythmics (Moderate Risk): QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of QT-prolonging Class IC Antiarrhythmics (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QT-Prolonging Inhalational Anesthetics (Moderate Risk): QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of QT-Prolonging Inhalational Anesthetics (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QT-prolonging Kinase Inhibitors (Moderate Risk): May increase QTc-prolonging effects of QT-prolonging Miscellaneous Agents (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QT-prolonging Miscellaneous Agents (Moderate Risk): May increase QTc-prolonging effects of Oxytocin. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QT-prolonging Moderate CYP3A4 Inhibitors (Moderate Risk): May increase QTc-prolonging effects of QT-prolonging Miscellaneous Agents (Moderate Risk). QT-prolonging Moderate CYP3A4 Inhibitors (Moderate Risk) may increase serum concentration of QT-prolonging Miscellaneous Agents (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QT-prolonging Quinolone Antibiotics (Moderate Risk): QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of QT-prolonging Quinolone Antibiotics (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QT-prolonging Strong CYP3A4 Inhibitors (Moderate Risk): May increase QTc-prolonging effects of QT-prolonging Miscellaneous Agents (Moderate Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Sertindole: May increase QTc-prolonging effects of QT-prolonging Agents (Moderate Risk). Risk X: Avoid
Succinylcholine: Oxytocin may increase neuromuscular-blocking effects of Succinylcholine. Risk C: Monitor
Sulprostone: May increase adverse/toxic effects of Oxytocic Agents. Risk X: Avoid
Thioridazine: QT-prolonging Agents (Moderate Risk) may increase QTc-prolonging effects of Thioridazine. Risk X: Avoid
Toremifene: QT-prolonging Miscellaneous Agents (Moderate Risk) may increase QTc-prolonging effects of Toremifene. Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
Small amounts of exogenous oxytocin are expected to reach the fetal circulation. When used as indicated, teratogenic effects would not be expected. Nonteratogenic adverse reactions are reported in the neonate as well as the mother.
Oxytocin is used for augmentation of labor in patients making slow progress through the first stage of spontaneous labor. The time to delivery is shortened by ~2 hours (Alhafez 2020).
When used for induction of labor, maternal and fetal conditions, cervical status, gestational age, and other factors should be considered. Indications for induction of labor are not absolute but may include abruptio placentae, chorioamnionitis, post-term pregnancy, preeclampsia/eclampsia, premature rupture of membranes, fetal compromise (eg, severe fetal growth restriction, isoimmunization, oligohydramnios), fetal demise, or maternal medical conditions (eg, diabetes mellitus, kidney disease, chronic pulmonary disease, chronic or gestational hypertension, antiphospholipid syndrome) (ACOG 2009). Oxytocin should not be used to induce labor when spontaneous labor or vaginal birth would otherwise be contraindicated (ACOG 2009; AWHONN [Simpson 2020]).
Although the prescribing information contains a boxed warning against use for non-medical induction of labor, oxytocin may be used off-label for the elective induction of labor at 39 weeks gestation. Details for this use come from the ARRIVE trial (A Randomized Trial of Induction Versus Expectant Management). The study included low risk nulliparous patients with singleton gestations. Eligible patients did not have conditions requiring delivery prior to 40 weeks gestation and had reliable information of gestational age based on ultrasound and date of last menstrual period. A specific dosing protocol for oxytocin was not used in the study. The study showed no statistical difference in the primary composite outcome of perinatal mortality and severe perinatal morbidity while noting that cesarean delivery rate was significantly lower in the induction of labor group. In addition, there was a lower rate of gestational hypertension and preeclampsia as well as a reduced need for neonatal respiratory support in the first 72 hours of life. The decision to induce labor in full-term nulliparous patients without a medical indication for delivery should be based on a shared decision-making process that compares the benefits and risks of labor induction and expectant management, the patients' birthing preferences, and the resources available (ACOG 2025; Grobman 2018; SMFM 2019).
Significant drug interactions exist (eg, dinoprostone, misoprostol), requiring dose/frequency adjustment or avoidance (ACOG 2009). Consult drug interactions database for more information.
Endogenous oxytocin mediates milk ejection. Administration of exogenous oxytocin may negatively impact breastfeeding. However, available studies have inconsistent results when evaluating the onset of lactogenesis, or the initiation and duration of breastfeeding. Outcomes may be influenced by study design, maternal dose, and indications for use (Buckley 2015; Erickson 2017; Fernández-Cañadas 2017; Fernández-Cañadas 2019; Gomes 2018).
Fluid intake and output during administration, uterine activity (tonus, amplitude, and frequency of contractions), maternal blood pressure; continuous electronic fetal heart rate monitoring in relation to uterine contractions.
Oxytocin stimulates uterine contractions by acting on receptors that trigger the release of intracellular calcium and local prostaglandin production. Oxytocin specific receptors are not present in the uterus until ~13 weeks' gestation and increase as pregnancy progresses and reach maximum concentration at term. Therefore, term pregnancies are more sensitive to lower oxytocin doses. The action of oxytocin is limited by the concentration of receptors in the smooth muscle of the uterus. Repeated doses may cause desensitization of the receptors and decreased response (Vallera 2017).
Onset of action: Uterine contractions: IM: 3 to 5 minutes; IV: ~1 minute
Duration: IM: 2 to 3 hours; IV: 1 hour
Half-life elimination: 1 to 6 minutes; decreased in late pregnancy and during lactation
Excretion: Urine (small amount unchanged)
