This review describes the origins, symptoms, and mechanisms of psychosocial stressors and compares these with symptoms induced by physical stressors. Diverse stressors can elicit symptoms that signal threats to homeostasis. Although physical and psychosocial pathways may differ in their afferent inputs, they can converge on shared efferent outputs. Recent advances suggest that identifying symptom origins helps link symptoms to relevant effector systems and guides treatment selection. Emerging bidirectional neuroimmune mechanisms, key moderators, and technological innovations further refine this framework, highlighting the need for personalized interventions to reduce disease chronicity. It is emphasized that identical symptoms may require different treatments depending on whether the triggering input is physical or psychosocial. Recognizing symptom origins is therefore essential to prevent diagnostic delay and avoid missed opportunities for timely care.