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Oxytocin

FDA Approved

Neurohypophysial Peptide | Social Bonding & Reproductive Hormone

Dose Intranasal: 20-24 IU; Injectable: 10-40 IU; Sublingual: 50-100 IU
Frequency As needed for social/sexual support, or 1-2x daily for anxiety/PTSD protocols; max 1 dose per 24hr for sexual function
Cycle As needed for research applications; 4-12 weeks for anxiety/autism protocols
Storage Refrigerate at 2-8°C; protect from light

Nine-amino-acid peptide hormone produced in hypothalamus, released by posterior pituitary. Functions in social bonding, trust, empathy, reproduction, childbirth, lactation. FDA-approved synthetically for labor induction and postpartum hemorrhage.

Mechanism of Action

Binds oxytocin receptors on uterine smooth muscle, triggering calcium influx and myometrial contractions. Stimulates prostaglandin release. In CNS, modulates GABAergic, serotonergic, dopaminergic neurotransmission; reduces cortisol and HPA axis activity.

Key Benefits

  • FDA-approved for labor induction with precise dosing via IV
  • Immediate onset in obstetric settings
  • Established safety profile in clinical use
  • Researched for anxiety, PTSD, autism, sexual dysfunction
Molecular Weight
1,007.19 Da
Chain Length
9 amino acids
Type
Cyclic nonapeptide
Amino Acid Sequence
One-letter: CYIQNCPLG?
H₂N
C 1
O C
N
Y 2
O C
N
I 3
O C
N
Q 4
O C
N
N 5
O C
N
C 6
O C
N
P 7
O C
N
L 8
O C
N
H
G 9
O C
N
H
? 10
COOH
Cys
1

Cysteine

Position 1

Tyr
2

Tyrosine

Position 2

Ile
3

Isoleucine

Position 3

Gln
4

Glutamine

Position 4

Asn
5

Asparagine

Position 5

Cys
6

Cysteine

Position 6

Pro
7

Proline

Position 7

Leu
8

Leucine

Position 8

Gly
9

Glycine

Position 9

NH2
10

NH2

Position 10

N-terminus C-terminus
Hydrophobic
Polar
Positive (+)
Negative (-)
Modified

Obstetric (FDA Approved)

  • Labor Induction

    Initiates or augments uterine contractions when vaginal delivery medically indicated.

  • Postpartum Hemorrhage Control

    Controls postpartum bleeding through uterine contraction stimulation during third stage.

  • Incomplete Abortion Management

    Adjunctive therapy for incomplete or inevitable abortion in second trimester.

Research/Emerging

  • Autism Spectrum Disorders

    Extensive research with mixed results on social functioning; optimal dosing unclear.

  • PTSD Augmentation

    Combined with exposure therapy; shows reduced PTSD/depression symptoms.

  • Social Anxiety

    Decreases amygdala reactivity to social threats; normalizes brain connectivity.

  • Sexual Function

    Improves libido, arousal, orgasm intensity in both sexes.

IV or IM administration in clinical settings. IV provides immediate onset; requires continuous infusion and monitoring for labor use.

GoalDoseFrequencyRoute
Labor Induction0.5-2 mU/min initial, titrate to 1-2 mU/min every 30-60 minContinuous IV infusionIV (diluted)
Postpartum Hemorrhage Prevention10 units IM or 10-40 units in IV solutionSingle dose after placental deliveryIM or IV infusion

Reconstitution Instructions

Materials Needed:
  • Oxytocin injection USP (10 units/mL)
  • Compatible IV solution (0.9% NaCl or Lactated Ringer's)
  • IV infusion pump (required)
  • Continuous fetal monitoring equipment
  1. 1 Hospital/clinical procedure—qualified healthcare professionals only
  2. 2 Dilute oxytocin in compatible IV solution per facility protocol
  3. 3 Typical dilution: 10 units in 1000mL = 10 mU/mL
  4. 4 Use infusion pump for precise rate control
  5. 5 Monitor uterine contractions and fetal heart rate continuously
Vasopressin (AVP)

Structurally similar; overlapping receptor affinity with potential additive effects.

monitor
Selank

Complementary anxiolytic effects—Selank modulates GABA; oxytocin acts on central receptors.

synergistic
PT-141 (Bremelanotide)

Complementary sexual function effects via different pathways.

synergistic
Kisspeptin

Both involved in reproduction; kisspeptin stimulates GnRH; oxytocin enhances arousal.

synergistic
BPC-157

No direct interactions; different mechanisms (tissue repair vs social function).

compatible
SSRI Antidepressants

SSRIs may affect endogenous oxytocin; combined use requires healthcare provider oversight.

monitor
Alcohol

Alcohol suppresses oxytocin release; reduces therapeutic effects.

avoid
Injectable

IV: 1-3 minute onset, 30-60 minute duration; IM: 3-5 minute onset

Intranasal

15-30 minute onset, peak 30-60 minutes, 2-4 hour duration

Sublingual

30-45 minute onset, peak ~60 minutes, 2-4 hour duration

Common Side Effects

  • Mild headache
  • Nasal irritation (intranasal)
  • Nausea or vomiting
  • Transient blood pressure changes

Stop Signs - Discontinue if:

  • Uterine hyperstimulation or fetal distress (injectable)
  • Severe or persistent headache
  • Signs of water intoxication (confusion, seizures, swelling)
  • Severe nasal irritation or bleeding
  • Allergic reaction (rash, breathing difficulty)

Contraindications

  • Certain obstetric conditions (see prescribing info)
  • Pregnancy (without medical supervision)
  • Active sinus infection (intranasal)
  • Severe hyponatremia

Good Signs

  • FDA-approved pharmaceutical product from licensed pharmacies (injectable)
  • Clear, colorless solution without particles or discoloration
  • Proper packaging with verified lot number, expiration, concentration
  • Licensed compounding pharmacy source with USP compliance

Warning Signs

  • Variable compounding quality between pharmacies
  • Nasal congestion reduces intranasal absorption
  • Sublingual has lower bioavailability than intranasal

Bad Signs

  • Cloudy, discolored, or particulate solution
  • From unlicensed or unverified sources
  • Improper storage or broken cold chain
  • Intranasal Oxytocin in Autism Spectrum Disorder
    (2021)

    N=290 children/adolescents; 48 IU daily; 24 weeks. Did not significantly improve social functioning vs placebo; highlights need for better patient selection.

  • Oxytocin Augmented Prolonged Exposure Therapy for PTSD
    (2019)

    Veterans with PTSD; 40 IU intranasal combined with PE therapy. Lower PTSD and depression symptoms; higher therapeutic alliance vs placebo.

  • Intranasal Oxytocin for Obesity
    (2024)

    N=61 adults with obesity; 24 IU four times daily; 8 weeks. No weight loss but significant reduction in caloric intake; improved mental health-related quality of life.

Disclaimer

This information is for educational and research purposes only. Consult a healthcare professional before use.