Vialwise
EN

Oxytocin

Oxytocin is a natural hormone made in the hypothalamus and released from the pituitary gland. It makes the uterus contract during birth and the breast release milk, and it also acts in the brain on social behavior. Synthetic oxytocin (Pitocin) is an approved hospital drug given by IV or intramuscular injection in labor and after delivery. Nasal sprays have been tested for autism and other conditions with mixed or negative results.

ApprovedChecked October 2026
Open the Oxytocin calculatorSources

Approval status

FDA-approved as Pitocin (oxytocin injection), given by IV infusion or intramuscular injection, for labor and after delivery. Syntocinon nasal spray is listed by the FDA as discontinued, so no nasal oxytocin is FDA-approved in the US.14

What it’s used or studied for

  • Approved use

    Starting or strengthening labor when there is a medical reason, given by IV infusion in hospital.1

  • Approved use

    Making the uterus contract after delivery to control bleeding after birth.1

  • Approved use

    Added treatment for incomplete or inevitable miscarriage.1

  • Human studies

    Nasal spray for children and teens with autism: a large trial found no improvement in social withdrawal compared with placebo, and a 2026 meta-analysis found no effect on social function.56

  • Human studies

    Nasal spray for other mental health conditions such as schizophrenia: trials are mixed, with at most small effects.7

Each label shows how strong the evidence is: an approved use, human studies, animal or lab studies only, or a popular claim with no published studies. Being studied is not the same as being proven safe or effective.

Side effects

Common

  • Nausea
  • Vomiting
  • Extra heartbeats (premature ventricular contractions)

Serious or rare

  • Overstimulation or rupture of the uterus
  • Water intoxication (low blood sodium) with seizures or coma
  • Severe allergic reactions (anaphylaxis)
  • Heavy bleeding after birth and a bleeding disorder (afibrinogenemia)
  • Bleeding in the brain (subarachnoid hemorrhage) and high blood pressure episodes
  • Slow heart rate, brain injury or death in the baby

These come from the Pitocin label for use in labor; the label does not rank them by frequency. In the large autism trial, side effects of the nasal spray were similar to placebo.15

Cautions

  • The label's boxed notice says Pitocin is not for elective induction of labor, meaning induction without a medical reason.1
  • For labor it should be given only by IV infusion in a hospital, with continuous observation by trained staff.1
  • Not for use when vaginal delivery is unsafe, the uterus is already overactive, or the baby is in distress and delivery is not imminent.1
  • It makes the body hold on to water; long infusions can cause water intoxication, especially when the person is also drinking fluids.1

Sources

  1. FDA label: Pitocin (oxytocin injection, USP) (DailyMed)
  2. PubChem CID 439302: Oxytocin
  3. UniProt P01178: Oxytocin-neurophysin 1 (human)
  4. Drugs@FDA: NDA 012285, Syntocinon (oxytocin) nasal solution, discontinued
  5. Sikich L et al. Intranasal oxytocin in children and adolescents with autism spectrum disorder (N Engl J Med, 2021)
  6. Fang G et al. Intranasal oxytocin on social interaction in autism: systematic review and meta-analysis of RCTs (Alpha Psychiatry, 2026)
  7. Bonnieux J et al. Does intranasal oxytocin reduce symptoms of mental disorders? A meta-analysis of clinical trials (Neurosci Biobehav Rev, 2026)

Spotted a mistake on this page? Report it. The email opens with the peptide and vial already filled in.