Oxytocin

Intranasal administration is the primary research route. Most human studies use 24 IU as a single dose. Some protocols use 8-12 IU twice daily, with target total daily doses up to 48 IU. FDA-approved as Pitocin for IV use in labor induction (dose varies by clinical protocol). Intranasal oxytocin for behavioral/psychological effects is investigational and not FDA-approved for those indications.

Binds to the oxytocin receptor, a class I G protein-coupled receptor coupled to Gq proteins, activating phospholipase C-beta and triggering intracellular calcium release. Requires Mg2+ and cholesterol as allosteric modulators for high-affinity binding.

Increases attention to social cues, enhances face recognition, and promotes prosocial behavior through central oxytocin receptor signaling in brain regions including the amygdala and prefrontal cortex.

Stimulates rhythmic uterine contractions during labor by activating OXTR on myometrial cells, the primary FDA-approved clinical use (Pitocin).

Triggers contraction of myoepithelial cells surrounding mammary alveoli, causing milk let-down during breastfeeding.

Intranasal oxytocin improves interpersonal trust, empathy, eye contact, and positive communication in research settings.

May reduce cortisol levels and anxiety, promoting a calm state. Effects are context-dependent and modulated by social environment.

Promotes pair bonding, maternal behavior, and romantic attachment through central oxytocin signaling. Well-established in animal models, supported in humans.

Oxytocin levels rise during arousal and orgasm. Supplementation may enhance sexual satisfaction and intimacy, though evidence is mixed.

Investigated for improving social responsiveness in autism spectrum disorder, with mixed results in clinical trials including a negative NEJM trial.

Study 41757114

Study 41756405

Study 41756013