Undergoing medical procedures is reported to cause stress and anxiety among many individuals.This can trigger the sympathetic nervous response, including decreased skin temperature, increased pulse, and increased blood pressure. While evolutionary advantageous, this response has deleterious effects on the healing process. Heightened stress levels can also trigger an increased release of cortisol, a naturally produced steroid hormone known to hinder the immune response. In response to high levels of stress, a patient's tolerance for pain decreases and the perceived pain level increases.