Evaluating the Specific Role of Endogenous Opioids as the Mechanism Underlying tAN-based Analgesia in Healthy Individuals
Medical University of South Carolina
Summary
This two-visit, randomized, double-blind, sham-controlled trial, uses a novel naloxone blockade model in 136 individuals to determine whether the analgesic effects of a 30-minute transcutaneous auricular neurostimulation (tAN) intervention are mediated through a release of endogenous opioids. Analgesic effects of four various stimulation interventions will be measured (auricular vagus, auricular trigeminal, combination, or sham) while varying the type of intravenous (IV) infusion (either naloxone or saline) a participant is administered to determine whether the analgesic effects are mitigated by pharmacological opioid receptor blockade.
Description
The demand for chronic pain treatment has demonstrated an unprecedented increase over the last several decades, in part contributing to an unsustainable surge in opioid prescriptions. Countless patients were escalated to prolonged, high-dose opioid regimens over years of treatment. By 2014, 5.4% of US adults were estimated to use prescription opioids on a long-term basis. As the harms of opioid proliferation became increasingly clear, a dramatic paradigm shift occurred in which these drugs came to be seen as often more dangerous than beneficial for chronic pain. New clinical guidelines highlig…
Eligibility
- Age range
- 18–65 years
- Sex
- All
- Healthy volunteers
- Yes
Inclusion Criteria: * Age 18-65 * Have the capacity and ability to provide one's own consent and sign the informed consent document Exclusion Criteria: * Contraindicated for MRI. * Any current or recent untreated medical, neurological, or psychiatric conditions * Metal implant devices in the head, heart or neck. * History of brain surgery. * History of myocardial infarction or arrhythmia, bradycardia. * Personal or family history of seizure or epilepsy or personal use of medications that substantially reduce seizure threshold (e.g., olanzapine, chlorpromazine, lithium). * Personal history o…
Interventions
- DrugNaloxone
A 0.15 mg/kg bolus dose of naloxone in 10ml normal saline will be administered via an intravenous (IV) line inserted into the antecubital vein of the non-dominant arm.
- DrugSaline
0.15mg/kg bolus of normal saline in 10ml normal saline will be administered via an intravenous (IV) line inserted into the antecubital vein of the non-dominant arm.
Location
- Medical University of South CarolinaCharleston, South Carolina