Essay from the year 2021 in the subject Medicine - Neurology, Psychiatry, Addiction, grade: 75%, University of East London, language: English, abstract: This paper is about the stress impact on the immune system from a psychoneuroimmunological perspective.Stress can be viewed as a psychological or physical strain that results in worry. Earlier species of mammals were subjected to environmental stressors such as wildlife predators that elicited physiological survival instincts. However, as contemporary mammals have evolved, so too has the environmental stimuli that trigger their physiological responses. When the body is subjected to distressing stimuli, the sympathetic-adreno-medullar (SAM) prepares the body for the sympathetic "fight-flight-freeze" response by releasing noradrenaline and norepinephrine. The heart rate and blood pressure increase, and muscles are activated. Simultaneously, the hypothalamus-pituitary-adrenal (HPA) releases glucocorticoids, which mobilizes cortisol to ensure the body is receiving a steady level of blood sugars to meditate the effects of stress. As the energy is directed elsewhere, resources are reduced in essential functions such as growth, repair, immunity and digestion. Notably, neurological pathways provide functionality and sustainability for the brain; however, when responding to distressing experiences, the brain can experience dysregulation, whereby the duration and magnitude of distress can alter the immune system's ability to reduce potentially detrimental health outcomes. The unpredictability of health outcomes can occur with short-term stressors as well as long-term life-altering stressors, such as post-traumatic stress disorder (PTSD) and chronic kidney disease (CKD), which are both explored in this work.