Non-invasive Vagus Nerve Stimulation (nVNS) for Post-Traumatic Stress Disorder (PTSD)

The goal of this clinical trial is to evaluate the safety and effectiveness of the gammaCore non-invasive vagus nerve stimulation (nVNS) device as an additional treatment for symptoms of post-traumatic stress disorder (PTSD) in adults. The vagus nerve connects the brain with many organs and systems in the body and plays a role in regulating stress and emotional responses. The gammaCore device is a handheld, rechargeable medical device that delivers gentle electrical stimulation to the vagus nerve through the skin on the side of the neck. By stimulating this nerve, the device may help reduce PTSD symptoms. gammaCore is cleared by the U.S. Food and Drug Administration (FDA) for the treatment and prevention of migraine and cluster headache. It has not yet been approved for the treatment of PTSD. This study is being conducted to better understand whether this type of stimulation may help improve PTSD symptoms and to evaluate its safety when used for this purpose. The main questions this study aims to answer are: * Is non-invasive vagus nerve stimulation safe for people with PTSD when used regularly at home? * Does treatment with the gammaCore device improve PTSD symptom severity over time? In this study, approximately 40 adults with PTSD will participate in an open-label pilot study. Participants will first complete a 4-week baseline period in which their PTSD symptoms are monitored. This allows researchers to understand each participant's symptoms before starting the intervention. Participants will then begin a 12-week treatment period using the gammaCore device at home. During this time, participants will apply the device to the side of the neck for short stimulation sessions each day as instructed by the study team. Participants will attend six study visits, some conducted remotely and some in person. These visits include screening, training on how to use the device, and follow-up assessments. During the study, participants will complete questionnaires and clinician-administered assessments that measure PTSD symptoms and quality of life. Researchers will also monitor participants for any side effects or medical problems related to the device. By collecting information on symptoms, safety, and device use, this study will help researchers understand whether non-invasive vagus nerve stimulation could become a useful treatment option for people living with PTSD.