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

This study is evaluating the Sparrow Link, a wearable device that delivers gentle electrical signals to nerves in the outer ear (a technique known as transcutaneous auricular neurostimulation, or tAN). The goal is to assess whether the device is feasible to use, acceptable to patients, and may help reduce opioid withdrawal symptoms in hospitalized adults being treated for opioid use disorder (OUD). Participants will be randomly assigned to receive either the active device or a sham (inactive) version. Neither participants nor their clinical teams will know which version is used. All participants will continue receiving standard hospital care for opioid withdrawal. Researchers will collect information on how long participants use the device, whether they stop using it early, and changes in withdrawal severity. The study will also examine pain, craving, mood, anxiety, heart rate variability, and opioid use during hospitalization.