Effects Of Intravenous Oxytocin On Peripheral Sensory Afferents Using Microneurography

What Was Tested

The trial (phase 2) is built around Oxytocin.

Does oxytocin raise the number of times a fiber which normally responds only to the thick bristle fires (sends a signal) after the heat pulses.

It had two arms (groups): Intravenous Oxytocin (experimental) and Intravenous Placebo (placebo comparator).

Saline will be administered as two 30-min IV infusions separated by 30-min, using the same volume of infusion solution and rates of administration as in the intravenous oxytocin intervention.

The registry classes the interventions as drug.

More on the Plan

Equal numbers of adult men and women; ages 18-65 will be recruited.

Study drug will be randomized and administered in two 30-minute infusions separated by the minutes.

Rapid rates of oxytocin infusion can cause acute adverse events in the first minutes of infusion.

Although these adverse events rapidly resolve despite continuing the infusion, one event (facial flushing) could negate the blind of study personnel.

Who Took Part

60 planned participants were the target.

It was open to people of any sex aged from 18 years up to 65 years.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Normal blood pressure (systolic 90-140 mmHg; diastolic 50-90 mmHg) resting heart rate 45-100 beats per minute) without medication. Proficient in Swedish or English.

The full record lists 4 inclusion and 10 exclusion criteria; among the exclusions: body mass index (bmi) \> 30; participants with neuropathy, chronic pain, diabetes mellitus, or taking benzodiazepines or pain medications on a daily basis; participants with current or history of ventricular tachycardia, atrial fibrillation or prolonged qt interval.

How the Study Was Run

The set-up was randomized, parallel-group and quadruple-blind.

Because people in this Oxytocin study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

The Oxytocin group and the comparison group ran side by side rather than switching.

Blinding on both sides kept the participants and researchers unaware of who received Oxytocin.

Those kept unaware of assignments: participant, care provider, investigator and outcomes assessor.

It started in 2025-10-22 with completion listed for 2027-06-01.

It ran at 1 site in Sweden.

Its stated primary purpose is basic science.

What Was Measured

Primary outcome: Number of nerve fiber discharges with von Frey filament application (time frame: 2-8 hours after start of the first IV infusion).

It also tracked 7 secondary outcomes, for example Verbal pain intensity score with von Frey filament application, Pattern of nerve fiber discharges with von Frey filament application, Number of nerve fiber burst discharges with tuning fork application, Number of nerve fiber discharges with warming and cooling, Number of nerve fiber discharges with soft brushing and Number of nerve fiber discharges with von Frey filament application: stimulus response relationship.

What This Means in Plain Language

Put simply, this is a phase 2, randomized trial of Oxytocin in 60 people.

It is still recruiting; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Oxytocin compound page, all human trials.