The Bonding Hormone
Oxytocin
At a glance
- What it is
- Intranasal oxytocin: 38 RCTs, good safety data, and no detectable subjective effect.
- Evidence
- Small human studiesHow the tiers workMacDonald et al., Psychoneuroendocrinology 2011 (PMID 21429671), reviewed 38 randomised controlled trials from 1990 to 2010 covering around 1,529 participants, 79% of them male, at 18–40 IU intranasally with some protocols running up to 182 total doses. Why this tier
- Half-life
- Plasma half-life is short, on the order of a few minutes after intravenous administration in non-pregnant adults.
- Routes
- Intranasal, Subcutaneous
- Category
- Sexual health, Support
- WADA
- We do not state a status
- Amino acids
- 9
Putting Oxytocin on a schedule, with the vial it comes from and a log of each dose, happens in the app: Claritide for iPhone.
Why this tier
MacDonald et al., Psychoneuroendocrinology 2011 (PMID 21429671), reviewed 38 randomised controlled trials from 1990 to 2010 covering around 1,529 participants, 79% of them male, at 18–40 IU intranasally with some protocols running up to 182 total doses. The conclusions are worth quoting in both directions: safe at 18–40 IU for short-term use in controlled research settings, no reliable side effects, and no detectable subjective changes in recipients, who could not distinguish oxytocin from placebo. A 2025 systematic review in older adults (9 RCTs, 331 participants, 24–72 IU) found no significant association with severe adverse outcomes; we could only read the abstract, so treat it as partial.
What it is
Oxytocin is a nine-amino-acid hormone with a large intranasal research literature and a well-conducted safety review behind it. That review is also the most interesting thing about it: across 38 randomised controlled trials, participants could not distinguish oxytocin from placebo and no reliable subjective changes were detected. It is safe at the doses studied, and it does not feel like anything.
How it works
Oxytocin is produced in the hypothalamus and released from the posterior pituitary. Peripherally it drives uterine contraction and milk ejection, which is what the obstetric drug is for. Centrally it modulates social cognition, trust, stress reactivity and pair bonding, which is what the intranasal research is about. The unresolved question underneath the whole intranasal literature is how much of an intranasal dose actually reaches the brain: oxytocin is a peptide and the nasal route is proposed to give partial direct access along olfactory and trigeminal pathways, but the fraction is not well established. That uncertainty is worth holding onto when reading any intranasal result, positive or null.
Commonly researched ranges
- Single-administration research dose18–40 IU
The dose band used across the 38 randomised trials in the 2011 systematic review, which concluded that oxytocin is safe at 18–40 IU for short-term use in controlled research settings.
- Repeated dosing (hypothalamic obesity trial)24 IU
A published clinical trial regimen. Repeated dosing above the customary 24 IU/day for prolonged periods is where the hyponatraemia concern sits.
| Phase | Amount | Frequency | Timing | Note |
|---|---|---|---|---|
| Single-administration research dose | 18–40 IU | Single administration | Not established in available literature | The dose band used across the 38 randomised trials in the 2011 systematic review, which concluded that oxytocin is safe at 18–40 IU for short-term use in controlled research settings. |
| Repeated dosing (hypothalamic obesity trial) | 24 IU | Four times daily at mealtimes, for 8 weeks | At mealtimes | A published clinical trial regimen. Repeated dosing above the customary 24 IU/day for prolonged periods is where the hyponatraemia concern sits. |
- Cycle guidance
- The research protocols are either single administrations or fixed courses of a few weeks. Our sources publish no cycling schedule for ongoing community use.
- Goals
- Libido
Where this sits with the FDA
FDA-approved drug product (obstetric injection)
Oxytocin is an approved prescription drug given intravenously or intramuscularly in obstetrics. That use is out of scope for this record and this page is not about it. The intranasal preparations used in research and sold by compounders are a different product for a different purpose, and intranasal oxytocin for social, cognitive or sexual effects is not an approved indication.
Primary sourceWADA status
Not named on the 2026 Prohibited List. Oxytocin holds human therapeutic approval, so the S0 catch-all does not obviously capture it. We could not determine a classification and do not state one.
We looked and could not resolve it. This is not the same as "not prohibited". Treat it as unresolved and check with your federation before competing.
Mixing recipes our sources document
Not established in available literature. Use the calculator with the figures printed on your own vial.
Open the calculator
Week by week
Not established in available literature.
Side effects
Rare
- No reliable side effects at research doses
- Hyponatraemia (low blood sodium)
Contraindications and interactions
Do not use if
Not established in available literature.
Interactions
Not established in available literature.
Absence from this list does NOT mean safety. It means lack of research.
Storage and cost
- Storage
- Sources disagree on the water. Our sourcing list puts oxytocin on the sterile-water list, dosing guides mix research oxytocin with bacteriostatic water, and we found no study of oxytocin in benzyl alcohol. The FDA labels do not settle it: Pitocin and a generic we read are ready-made solutions preserved with chlorobutanol, not benzyl alcohol. Claritide takes the cautious side: sterile water, which means a 24-hour window, not 28 days. No source we hold states a vial and diluent pairing, so we publish no preset.
- Cost
- Not established in available literature
Oxytocin in full
Why this record exists now
Our storage rules already named oxytocin, since it is on our list of compounds that get sterile water rather than bacteriostatic water, and we had no record for it. A safety rule that points at a compound with no page is a loose end.
What the evidence says, in both directions
The anchor is MacDonald et al., Psychoneuroendocrinology 2011, PMID 21429671: a systematic review of 38 randomised controlled trials published between 1990 and 2010, covering around 1,529 participants, 79% of them male. Doses of 18 to 40 IU intranasally for single administration, with some protocols running up to 182 total doses.
Its conclusions:
- Safe at 18–40 IU for short-term use in controlled research settings.
- No reliable side effects.
- No detectable subjective changes in recipients. Participants could not distinguish oxytocin from placebo.
- Only three case reports of adverse reactions were identified in the whole literature, all linked to misuse or longer-term unauthorised use.
That is an unusual combination and it is the honest summary of this compound: an extensively studied intervention with a good safety record and no felt effect. A drug that people cannot tell they have taken is not necessarily doing nothing, since the research measures social and cognitive endpoints rather than vibes, but it does mean that anyone reporting a dramatic subjective response to intranasal oxytocin is reporting something 38 trials did not find.
A 2025 systematic review in older adults, covering 9 randomised trials and 331 participants at doses of 24 to 72 IU, likewise found no significant association with severe adverse outcomes. We could only read the abstract, so that one is partial.
Dosing
The research band is 18 to 40 IU intranasally for a single administration. For repeated dosing there is a published trial regimen: 24 IU at mealtimes, four times daily for 8 weeks, in hypothalamic obesity.
The monitoring note
Hyponatraemia, low blood sodium, is flagged as a concern when intranasal dosing exceeds the customary 24 IU per day over prolonged periods. We could not verify this at primary-source level. It is a recognised class effect of oxytocin and it is the kind of thing worth watching for rather than ignoring, so it ships as a monitoring note with its uncertainty attached rather than as a contraindication or as silence.
Storage
For the water, sources disagree. Our list says sterile water, dosing guides say bacteriostatic water, and we found no study of oxytocin in benzyl alcohol. The approved product does not answer it either: Pitocin and a generic we read are ready-made solutions preserved with chlorobutanol, not benzyl alcohol. Claritide takes the cautious side: sterile water and a 24-hour window, not bacteriostatic water and 28 days.
What this page is not about
Oxytocin is also a prescription obstetric drug given intravenously and intramuscularly to induce labour and control postpartum bleeding. That use is entirely out of scope here, requires a clinical setting, and has nothing to do with what people are buying intranasal oxytocin for. We name it so this record does not read as a page about a birth drug.
Sources
- 1MacDonald et al., 2011 · A review of safety, side-effects and subjective reactions to intranasal oxytocin in human research, Psychoneuroendocrinology 36(8):1114–1126
- 2Australasian Psychiatry, 2025 · systematic review of intranasal oxytocin in older adults (abstract only)
- 3Journal of the Endocrine Society, 2023 · intranasal oxytocin 24 IU four times daily in hypothalamic obesity
- 4Par Health · Pitocin (oxytocin injection, USP) prescribing information on DailyMed, revised May 2026 (checked 27 Sep 2026)
- 5Fresenius Kabi · Oxytocin Injection, USP (synthetic) prescribing information on DailyMed, listing revised January 2026 (checked 27 Sep 2026)
Every record in this library is free to read, and it stays free. Your own schedule, vials and log live in the app: Claritide for iPhone.