Salivary and plasmatic oxytocin are not reliable trait markers of the physiology of the oxytocin system in humans.

Martins D, Gabay AS, Mehta M, Paloyelis Y

eLife11 Dec 2020Cited by 77 (Europe PMC)

PMID33306025PMCIDPMC7732341DOI10.7554/elife.62456PepBankPUB-33306025

Summary

Single measurements of salivary and plasmatic oxytocin are used as indicators of the physiology of the oxytocin system. However, questions remain about whether they are sufficiently stable to provide valid trait markers of the physiology of the oxytocin system, and whether salivary oxytocin can accurately index its plasmatic concentrations. Using radioimmunoassay, we measured baseline plasmatic and/or salivary oxytocin from two independent datasets. We also administered exogenous oxytocin intravenously and intranasally in a triple dummy, within-subject, placebo-controlled design and compared baseline levels and the effects of routes of administration. Our findings question the use of single measurements of baseline oxytocin concentrations in saliva and plasma as valid trait markers of the physiology of the oxytocin system in humans. Salivary oxytocin is a weak surrogate for plasmatic oxytocin. The increases in salivary oxytocin observed after intranasal oxytocin most likely reflect unabsorbed peptide and should not be used to predict treatment effects.

CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study3

1 result from studies that gave the peptide. 1 result from people.

01HumanOther designPharmacokinetics
In humans, salivary oxytocin concentrations increased after intranasal oxytocin, which most likely reflects unabsorbed peptide.
In plain wordsIn people, oxytocin in saliva rose after oxytocin nasal spray, most likely because of unabsorbed peptide rather than uptake into the body.
Peptide
Oxytocin
Outcome
IncreaseSalivary oxytocin after intranasal oxytocin
Study
n: not reported in source
Comparator
Placebo
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · intranasalAs given in this study (human).
Source sentences
Summary
The increases in salivary oxytocin observed after intranasal oxytocin most likely reflect unabsorbed peptide and should not be used to predict treatment effects.
2 context sentences(design, population, supporting numbers)
Summary · context
We also administered exogenous oxytocin intravenously and intranasally in a triple dummy, within-subject, placebo-controlled design and compared baseline levels and the effects of routes of administration.
Summary · context
Using radioimmunoassay, we measured baseline plasmatic and/or salivary oxytocin from two independent datasets.
Show in the study text Report a problemFND-3330602501

Natural levels measured2

These results measure the body's own peptide. Nobody was given the peptide. They are not evidence about taking it. They are left out of key results, evidence counts and charts.

02HumanEndogenous levelObservational studyOther
In humans, baseline salivary oxytocin was a weak surrogate for baseline plasmatic oxytocin.
In plain wordsIn people, the body's own oxytocin in saliva was a weak stand-in for the body's own oxytocin in blood.
Peptide
Oxytocin
Outcome
Not applicableSalivary oxytocin as surrogate for plasmatic oxytocin
Study
n: not reported in source
Outcome group
Pharmacokinetics · Pharmacology
Source sentences
Summary
Salivary oxytocin is a weak surrogate for plasmatic oxytocin.
1 context sentence(design, population, supporting numbers)
Summary · context
Using radioimmunoassay, we measured baseline plasmatic and/or salivary oxytocin from two independent datasets.
This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.
Show in the study text Report a problemFND-3330602502
03HumanEndogenous levelObservational studyOther
In humans, single baseline measurements of salivary and plasmatic oxytocin were not valid trait markers of the physiology of the oxytocin system.
In plain wordsIn people, one measurement of the body's own oxytocin in saliva or blood was not a valid marker of how the oxytocin system works.
Peptide
Oxytocin
Outcome
Not applicableSingle baseline oxytocin measurements as trait markers
Study
n: not reported in source
Outcome group
Pharmacokinetics · Pharmacology
Source sentences
Summary
Our findings question the use of single measurements of baseline oxytocin concentrations in saliva and plasma as valid trait markers of the physiology of the oxytocin system in humans.
1 context sentence(design, population, supporting numbers)
Summary · context
Using radioimmunoassay, we measured baseline plasmatic and/or salivary oxytocin from two independent datasets.
This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.
Show in the study text Report a problemFND-3330602503

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 2Current
11 Oct 2026, 01:30 UTC
Study results updated
Version 1
9 Oct 2026, 02:48 UTC
First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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