Evaluating the Efficacy of Intranasal Oxytocin on Pain and Function Among Individuals Who Experience Chronic Pain: a Multisite, Placebo-controlled, Blinded, Sequential, Within-subjects Crossover Trial
One in five Canadians live with chronic pain, defined as pain that lasts longer than 3-months. Living with chronic pain has a detrimental impact on physical health, emotional health, and quality of life. Current treatments rarely result in pain relief and often do not meaningfully improve physical or emotional function. Further, medication used to treat pain often causes unwanted symptoms. There is a need to develop new treatments to help manage chronic pain. The use of a nasal spray containing manufactured oxytocin may improve pain management. Oxytocin is produced in the human body and has been shown to impact the pain pathway in animals. Our project tests whether the use of a nasal spray containing oxytocin will improve pain and function in men and women who live with chronic pain. Men and women with chronic nerve, muscle, or pelvic pain will be recruited in Vancouver, Calgary, and St. John's. Each person will be assigned to complete three interventions in a random order. Each intervention involves using a nasal spray twice per day over a 2-week period. The nasal spray will contain a small dose of oxytocin during one intervention and a medium dose during the second intervention. The nasal spray during the final intervention will have no oxytocin. This final intervention is a control intervention that will allow us to measure the effect of simply taking a nasal spray (i.e., the impact of expectation). Participants and researchers will not know which interventions involve the use of oxytocin. Participants will rate their pain and function each day throughout each task. The investigators will calculate each person's score on pain and function. The investigators will test whether participants report less pain and better function when they use oxytocin compared to the control. The results of this project may improve pain, function, and quality of life among those who live with chronic pain.
• Adult (\> 18 years) men and premenopausal women;
• On stable medication for pain management for 3 months or more with no anticipated changes during the 10-weeks of this trial;
• Moderate pain at baseline (i.e., a score of 4-8 on a 10-point numeric rating scale) to prevent floor and ceiling effects.
• Can commit the use of two forms of effective contraception (e.g., barrier methods), or one highly effective method, including abstinence, intrauterine device, intrauterine system (IUS), vasectomy, tubal ligation, or hormonal contraceptive (e.g., combined oral contraceptives, patch, vaginal ring, injectables, and implants)
• Surrey, BC: Men and women with primary neuropathic pain - pain arising as a direct consequence of a lesion or disease affecting the central or peripheral nervous system - will be eligible. Neuropathic pain will be screened for using a score of 3+ on the Douleur Neuropathique 4 Interview, and confirmed through investigation (e.g., electromyography).
• Calgary, AB: Women with chronic (intermittent or constant) pelvic musculoskeletal pain (i.e., located primarily in the pelvic region and reproducible on palpation of the pelvic floor) who have not received a hysterectomy will be eligible. Women with a primary diagnosis of endometriosis, dysmenorrhea, functional bowel disorder, interstitial cystitis, fibromyalgia or sacroiliac instability as defined by European Guidelines, will be excluded.
• Carbonear NL: Men and women with primary musculoskeletal pain of back, neck, or shoulder origin will be eligible. Pain will be assessed using the BPI-SF and confirmed through physical examination.