Rejection sensitive dysphoria is not a formal diagnosis, but rather one of the most common and disruptive manifestations of emotional dysregulation — a common but under-researched and oft-misunderstood symptom of ADHD, particularly in adults. Rejection sensitive dysphoria is a brain-based symptom that is likely an innate feature of ADHD. Though the experience of rejection sensitive dysphoria can be painful and even traumatic, RSD is not thought to be caused by trauma.