oxytocin

Oxytocin is a synthetic form of the hormone oxytocin, which is naturally produced by the brain’s hypothalamus region and secreted into the bloodstream by the pituitary gland. It is used to induce or improve uterine contractions during childbirth and prevent hemorrhage. It can also be used to remove the contents of the uterus after a termination of pregnancy.

Oxytocin stimulates uterine contractions by binding to oxytocin receptors in the uterine muscle wall, which increases calcium influx in the uterine muscle cells. The concentration of oxytocin receptors in the uterus varies between individuals and increases during pregnancy.

Oxytocin also causes contraction of the myoepithelial cells in the breasts to facilitate milk ejection. It has additional effects on fluid balance, blood flow, and functions as a neurotransmitter in the brain, influencing behaviors such as romantic attachment, sexual arousal, trust, and bonding.

Oxytocin is approved for use in certain medical conditions to induce labor in pregnant women:

• Preeclampsia, diabetes, Rh factor incompatibility, premature rupture of membranes

Warnings

• Do not use oxytocin for elective induction of labor
• Administer oxytocin intravenously under medical supervision
• Avoid oxytocin if there is hypersensitivity to it or if certain conditions are present, such as fetal distress, inadequate uterine activity, hypertonic uterus, cephalopelvic disproportion, unfavorable fetal position, obstetrical emergencies, medical conditions precluding vaginal delivery, and pregnancy or labor complications

Side effects

Common side effects of oxytocin include:

Mother:

• Allergic reactions, premature ventricular contractions, postpartum hemorrhage, pelvic hematoma, cardiac arrhythmia, subarachnoid hemorrhage, fatal afibrinogenemia, hypertensive episodes, nausea, vomiting, rupture of the uterus

Fetal/neonate:

Due to induced uterine contractions:

• Bradycardia, arrhythmias, fetal hypoxia, fetal hypercapnia, CNS damage, fetal death, neonatal seizures (rare)

Due to use of oxytocin in the mother:

• Low Apgar scores at five minutes, neonatal jaundice, neonatal retinal hemorrhage, perinatal liver necrosis

This is not a complete list of all side effects or adverse reactions. Contact your doctor for medical advice or report side effects to the FDA.

Dosages

Injectable Solution:

Postpartum Hemorrhage:

• 10 units intramuscularly (IM) after delivery of the placenta
• Add 10-40 units to 1000 mL of non-hydrating intravenous (IV) solution and infuse at the necessary rate

Labor Induction:

• 0.5-1 mUnit/min IV, titrate as needed

Incomplete or Inevitable Abortion:

• 10-20 mUnit/min, not to exceed 30 units/12 hours

Monitor:

• Intrauterine pressure, fetal heart rate

Overdose

• Oxytocin overdose may result from excess dosage or uterine hypersensitivity.
• Excessive stimulation of uterine contractions can lead to complications for both the mother and fetus, including labor issues, uterine rupture, and water intoxication with convulsions.
• Treatment involves immediate discontinuation of oxytocin and supportive care for mother and newborn.

Drug interactions

Inform your doctor of all medications you are currently taking to check for potential drug interactions.

• Oxytocin has no known severe interactions with other drugs.
• Serious interactions include fexinidazole, lefamulin, mefloquine, and misoprostol.

It is important to always inform your healthcare provider about all medications you use, including prescription and over-the-counter drugs.

Pregnancy and breastfeeding

• Oxytocin may be used in approved indications during pregnancy at term or near term.
• It should not be used otherwise during pregnancy or while breastfeeding.
• Delay breastfeeding for at least 1 day after discontinuation of oxytocin.

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Summary

Oxytocin is a synthetic form of the hormone oxytocin used to induce or improve uterine contractions during delivery and prevent hemorrhage. Common side effects include allergic reactions, cardiac issues, bleeding, hypertension, and rupture of the uterus. It should not be used during pregnancy or while breastfeeding.

Oxytocin is a synthetic form of the hormone oxytocin used to induce or improve uterine contractions during delivery and prevent hemorrhage. Common side effects include allergic reactions, cardiac issues, bleeding, hypertension, and rupture of the uterus. It should not be used during pregnancy or while breastfeeding.