Oxytocin
Also known as: Oxytocin
Oxytocin is a nine-amino-acid hypothalamic neuropeptide hormone involved in social bonding, reproduction, and uterine contraction. It is FDA-approved clinically for labor induction and is studied for its effects on trust, intimacy, and social behavior.
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Mechanism of Action
Oxytocin binds the oxytocin receptor (OXTR), a G-protein-coupled receptor that signals primarily through Gq/11 to activate phospholipase C, raising intracellular calcium and driving smooth-muscle contraction in the uterus and mammary myoepithelium. Centrally released oxytocin modulates limbic circuitry in the amygdala, nucleus accumbens, and hypothalamus, influencing social salience, pair bonding, and stress reactivity. It also interacts weakly with vasopressin receptors, which contributes to some cardiovascular and antidiuretic effects.
- Half-life
- Approximately 1 to 6 minutes (intravenous); intranasal central effects last longer
- Administration Routes
- intranasal, subcutaneous
- Research Status
- Clinical
Reported Benefits
- Stimulates uterine contractions for labor induction and postpartum hemorrhage control
- Triggers the milk let-down (ejection) reflex during lactation
- Studied for enhancing social bonding, trust, and empathy
- May reduce anxiety and dampen the stress response
- Investigated as an adjunct in conditions involving social deficits
- Explored for effects on libido and orgasmic response
Potential Side Effects
- Nausea and abdominal cramping
- Headache
- Hyponatremia and water retention with high or prolonged dosing
- Hypotension or reflex tachycardia
- Uterine hyperstimulation in obstetric use
Common Dosing
In research literature, intranasal oxytocin is typically studied at 16-40 IU per administration. (Oxytocin is dosed in international units, not micrograms; mass conversions circulating online are unreliable.) For research use only.
The dosing information above is aggregated from research literature and anecdotal community reports for educational purposes only. It is not a recommendation, prescription, or medical advice. Peptides are sold as research chemicals only and are not intended for human use.
Contraindications
- Pregnancy outside of supervised obstetric settings
- History of hyponatremia or conditions of fluid overload
- Known hypersensitivity to oxytocin
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