Sparrow Link Neuromodulation Device for Opioid Withdrawal Management in Hospitalized Adults With Opioid Use Disorder

Opioid withdrawal is a major barrier to the initiation and continuation of treatment for opioid use disorder (OUD), particularly during hospitalization. Symptoms of withdrawal may lead patients to decline initiation of treatment or leave against medical advice. Neuromodulation strategies, such as transcutaneous auricular neurostimulation (tAN), are emerging as potential adjuncts to standard pharmacologic management. tAN targets cranial nerves via stimulation of the auricular branch of the vagus nerve and other nerve branches in the external ear. The Sparrow Link is a wearable tAN device intended for short-term use in clinical environments and is being evaluated in this study for its role in reducing withdrawal symptoms and enhancing the inpatient care experience. This is a double-blind, sham-controlled, randomized pilot trial designed to evaluate the feasibility, acceptability, and preliminary effectiveness of the Sparrow Link device in hospitalized adults with OUD undergoing opioid withdrawal. The study is being conducted at UPMC Presbyterian and Montefiore hospitals with clinical oversight by the STARS (Substance Treatment and Recovery Service) addiction medicine consult team. Eligible participants will be randomized 1:1 to receive either active or sham tAN stimulation. All participants will receive standard hospital-based opioid withdrawal management, including pharmacologic treatment as clinically indicated (e.g., methadone, buprenorphine, or full opioid agonists). The device is applied and monitored by trained research staff during daytime hours. The study includes both implementation and effectiveness endpoints. Primary implementation outcomes include device usage consistency and early device discontinuation. The primary effectiveness outcome is change in opioid withdrawal severity, as measured by the Clinical Opiate Withdrawal Scale (COWS). The study also includes secondary measures of pain, anxiety, depressive symptoms, craving, heart rate variability, and opioid use during hospitalization. Exploratory outcomes include referral to follow-up care, intent to continue device use, and qualitative feedback from providers regarding device feasibility and integration into clinical workflow.