Evaluating the Efficacy of Intranasal Oxytocin Among Individuals With Persistent Pain

This study is a placebo-controlled, double-blind, within-participants crossover investigation of the effect of intranasal oxytocin on pain and function among women with chronic pelvic pain.

Study Overview

• Status: Completed
• Conditions: Chronic Pain; Pelvic Pain
• Intervention / Treatment: Drug: Placebo; Drug: Intranasal Oxytocin

Detailed Description

1. Rationale: Oxytocin (OT) is a neuropeptide produced in the supraoptic and paraventricular nuclei of the hypothalamus. There exists at least three plausible mechanisms through which OT may decrease pain sensitivity. In brief, the first mechanism involves spinal signaling. A direct hypothalamo-spinal projection originating from the paraventricular nucleus transports OT, to the dorsal horn (Lamina-I, II, and IV), an area containing OT receptors that influence glutamate and GABA cellular signaling. The second mechanism involves an indirect pathway via the endogenous opioids. Evidence suggests that OT binds to opioid receptors and may also stimulate endogenous opioid release in the brain. Finally, OT may decrease pain by improving mood, decreasing anxiety, and mitigating the stress response.

   Thirty-three animal investigations have assessed OT-pain relationships with 29 reporting that exogenous administration and higher endogenous levels decreased pain. There is a lack of clarity of an OT-pain association in the human literature due to a paucity of methodologically rigorous trials. Thus far, OT administration has been reported to lower pain sensitivity among patients experiencing chronic back pain, headache, constipation, and colon pain. To date, no research has evaluated the association between intranasal OT and chronic pelvic pain. The association between OT and pain may be different in women with pelvic pain relative to other chronic pain conditions because of a potential peripheral OT-pain pathway. There is an abundance of OT receptors in the uterus, and OT is a potent uterogenic agent that is clinically used in large doses to stimulate uterine contractions and induce labor. While OT does not cross the blood-brain-barrier, the central administration of intranasal OT increases central and blood-plasma OT concentrations. Thus, intranasal OT administration may be associated with pain through central and peripheral pathways; however uterine contractions with 24IU doses of intranasal OT occur in only 1 in every 100-1000 people.

2. Research questions and objectives: This research is a pilot study of the efficacy of intranasal OT at improving pain and function among women with chronic pelvic pain of primarily musculoskeletal origin.
3. Design: This study will utilize a double-blind, placebo-controlled, within-subjects crossover design. Participants will complete 6-weeks of testing consisting of two 2-week intranasal administrations separated by a 2-week washout period

• Study Type: Interventional
• Enrollment (Actual): 24
• Phase: Phase 2; Phase 3

Contacts and Locations

Study Locations

• Canada
  • Alberta
    • Calgary, Alberta, Canada, T2N 1N4
      • Behavioural Medicine Laboratory

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Non-menopausal women with chronic pelvic musculoskeletal pain (i.e., pain exceeding 6-months in duration that is located primarily in the pelvic region and reproducible on palpation to the muscles spanning the pelvic floor) will be eligible to participate if they: 1) have regular menstrual periods (monthly within a 21-35 day range); 2) using a permanent or barrier form of contraception; 3) can commit not to change their medication during the 6-weeks of this study; and 4) have a moderate amount of pain at baseline (i.e., a pain score of 4-7 out of 10 on a numeric rating scale). A baseline pain score of 4-7 out of 10 was selected to prevent floor and ceiling effects and ensure that participants have room to change throughout the course of the study.

Exclusion Criteria:

• Muscle pain as a result of systemic disease, scoring positive on a urine pregnancy test, concurrent use of another nasal spray, nasal pathology (e.g., ears, nose, and throat diagnosis), diabetes insipidus, previous or concurrent use of narcotics delivered intranasally (e.g., cocaine), are contemplating pregnancy, or who have sacroiliac instability as defined by the European Guidelines. Women will also be excluded with they have a primary diagnosis of endometriosis, dysmenorrhea, interstitial cystitis, functional bowel disorder, fibromyalgia or neuropathic pain.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intranasal Oxytocin; Oxytocin nasal spray delivered bi-daily over a 14-day period at 24-IU per dose	Drug: Intranasal Oxytocin; Intranasal oxytocin (Syntocinon; Novartis, Switzerland); Other Names: Syntocinon
Placebo Comparator: Placebo; Placebo nasal spray containing the same ingredients as the active nasal spray minus the oxytocin and packaged in an identical bottle. To be delivered bi-daily over a 14-day period at 24-IU per dose	Drug: Placebo; Placebo nasal spray

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Self-reported pain	The Brief Pain Inventory - Short Form	14-days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Self-report positive and negative affect	Positive and Negative Affect Scale	14-days
Self-report depressed mood, anxious mood, and stress	Depression Anxiety Stress Scale	14-day
Self-report sleep	Medical Outcomes Study Sleep Scale	14-day

Collaborators and Investigators

• Sponsor: University of Calgary

Publications and helpful links

General Publications

• Flynn MJ, Campbell TS, Robert M, Nasr-Esfahani M, Rash JA. Intranasal oxytocin as a treatment for chronic pelvic pain: A randomized controlled feasibility study. Int J Gynaecol Obstet. 2021 Mar;152(3):425-432. doi: 10.1002/ijgo.13441. Epub 2020 Dec 8.
• Rash JA, Toivonen K, Robert M, Nasr-Esfahani M, Jarrell JF, Campbell TS. Protocol for a placebo-controlled, within-participants crossover trial evaluating the efficacy of intranasal oxytocin to improve pain and function among women with chronic pelvic musculoskeletal pain. BMJ Open. 2017 Apr 16;7(4):e014909. doi: 10.1136/bmjopen-2016-014909.

Study record dates

Study Major Dates

• Study Start: November 1, 2016
• Primary Completion (Actual): December 1, 2018
• Study Completion (Actual): December 1, 2018

Study Registration Dates

• First Submitted: August 30, 2016
• First Submitted That Met QC Criteria: September 2, 2016
• First Posted (Estimate): September 5, 2016

Study Record Updates

• Last Update Posted (Actual): May 18, 2022
• Last Update Submitted That Met QC Criteria: May 16, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Chronic Pain; Pelvic Pain; Physiological Effects of Drugs; Reproductive Control Agents; Oxytocics; Oxytocin
• Other Study ID Numbers: CHREB16-0334

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided