Oxytocin
Also called Pitocin (prescription injection)
A peptide hormone with established hospital uses in childbirth and a much less settled role in research on social behavior, appetite and sexual function. The "love hormone" nickname oversimplifies the evidence.
Overview
What it is
A nine-amino-acid hormone made in the brain. Pitocin is a specific prescription formulation for IV use in obstetric care.
How it works
Oxytocin stimulates uterine contractions, which is the basis of its approved uses. Nasal sprays change some brain blood-flow measures, but delivery route strongly affects results.
What the research shows
A 2021 trial in children and teens with autism found nasal oxytocin did not beat placebo after 24 weeks. A 2024 obesity trial found no weight-loss benefit after 8 weeks. A trial in women found no significant improvement in sexual function versus placebo; a separate vaginal-gel study in postmenopausal women reported improvements in vaginal atrophy. Reviews describe inconsistent anxiety findings.
Studied for
- Labor induction and postpartum bleedingapproved, hospital
- Autism social symptomsnegative trial
- Weight lossnegative trial
- Sexual functionmixed
Safety and regulatory status
Safety and side effects
In obstetric use, the label warns about excessive contractions, fetal complications and water intoxication. Nasal trials showed similar side-effect rates to placebo in their settings, but that does not establish safety for long-term self-directed use. It should not be used outside medical care during pregnancy.
Regulatory status
FDA approved (Pitocin) only for specific obstetric uses under hospital supervision.
Mixing and dosing reference
Reference information only. Read before using this section.
Oxytocin (10 mg Vial) Dosage Protocol
- Vial
- 10 mg Oxytocin
- Add diluent
- 3 mL
- Concentration
- 3.33 mg/mL
- 1 unit (U-100)
- 33.33 mcg in 0.01 mL
- Route
- Subcutaneous
- How often
- Once per day (subcutaneous); rotate injection sites.
- Typical range
- 100–500 mcg once daily (gradual titration).
- Cycle length
- 8–12 weeks; optional extension to 16 weeks.
Standard / Gradual Approach
| Week | Daily Dose (mcg) | Units (per injection) (mL) |
|---|---|---|
| Weeks 1–2 | 100 mcg | 3 units (0.03 mL) |
| Weeks 3–4 | 200 mcg | 6 units (0.06 mL) |
| Weeks 5–6 | 300 mcg | 9 units (0.09 mL) |
| Weeks 7–8 | 400 mcg | 12 units (0.12 mL) |
| Weeks 9–12 | 500 mcg | 15 units (0.15 mL) |
Human Oxytocin Dosing Evidence
| Study | Route and amount | Design | What it established |
|---|---|---|---|
| Albinni et al. | One 4 mcg subcutaneous injection in 2 mL | Randomized, double-blind crossover experiment in 18 adults | Heat-pain intensity and unpleasantness decreased locally; the study did not test a repeated daily schedule. |
| Plessow et al. | 24 IU intranasally four times daily | Eight-week randomized placebo-controlled trial in 61 adults with obesity | Body-weight change did not differ from placebo; caloric intake at a test meal decreased as a secondary outcome. |
| MacDonald et al. | Intranasal studies, often 18–40 IU per administration | Systematic safety review | Short-term exposure was generally well tolerated, but long-term safety and injectable schedules were not established. |
| Hallschmid et al. | One 24 IU intranasal administration | Randomized placebo-controlled crossover study in fasting men | Test-meal caloric intake decreased; the result did not establish chronic subcutaneous dosing. |
| Brede et al. | 24 IU intranasally before an oral glucose tolerance test | Double-blind crossover study in men with type 2 diabetes | Acute glucose tolerance did not improve. |
| Pedersen et al. | 0.2 IU/min intravenous infusion | Randomized double-blind crossover study in adults with obesity | The IV experiment did not support treating intranasal, IV, and subcutaneous amounts as equivalent. |
How to mix
- Draw 3.0 mL bacteriostatic water with a sterile syringe.
- Inject slowly down the vial wall; avoid foaming.
- Gently swirl/roll until dissolved (do not shake).
- Label and refrigerate at 2–8 °C (35.6–46.4 °F), protected from light.
Dosing details
- Start: 100 mcg daily for 2 weeks; increase to 200 mcg for weeks 3–4.
- Titration: Increase by ~100 mcg every 2 weeks as tolerated (300 mcg weeks 5–6, 400 mcg weeks 7–8).
- Target: 500 mcg daily by weeks 9–12 (typical upper limit for research protocols).
- Frequency: Once per day (subcutaneous); rotate injection sites.
- Cycle Length: 8–12 weeks; optional extension to 16 weeks.
- Timing: Any consistent time; oxytocin has rapid clearance, so effects are acute per dose.
Protocol source: PeptideDosages.com
Common questions
Is Pitocin the same as oxytocin?
Pitocin is one prescription formulation of synthetic oxytocin.
Does nasal oxytocin reach the brain?
Studies show some brain effects, but they differ by delivery route and do not prove a clinical benefit.
Can oxytocin improve relationships?
Bonding research does not establish it as a relationship aid.
Related in Hormones and Reproductive Health
Sources and further reading (6)
- DailyMed. Pitocin prescribing information.
- Sikich L, et al. Intranasal oxytocin in children and adolescents with autism. NEJM, 2021.
- Intranasal oxytocin for obesity. NEJM Evidence, 2024.
- Muin DA, et al. Long-term intranasal oxytocin and sexual dysfunction in women. Fertil Steril, 2015.
- Martins DA, et al. Route of administration and oxytocin-induced brain blood flow. Nat Commun, 2020.
- Source summary: PeptideDosages.com research overview (rewritten for NVO).
Laboratory research material: Oxytocin Research Use Only