Combat and Operational Stress Reactions

Combat and operational stress reaction (COSR) is the term used to describe an acute stress reaction in the combat environment and can include virtually any symptom and sign, including physical and neurological symptoms, resulting from exposure to extremely stressful events or combat experiences. It may result from specific traumatic experiences in combat or exhaustion due to the cumulative effects of one or more factors, including sleep deprivation, extreme physical stress, poor sanitary conditions, limited caloric intake, dehydration, or extremes of environmental conditions.[ Reference 1 ] Combat stressors include singular incidents that have the potential to significantly impact the unit or service members experiencing them. They may come from a range of possible sources while performing military missions. Operational stressors may include multiple combat stressors or prolonged exposures due to continued operations in hostile environments.[ Reference 2 ] Examples of combat and operational stressors include:[ Reference 2 ]

Combat Stressors

  • Personal injury
  • Killing of combatants
  • Exposure to blasts or incoming fire
  • Witnessing the death of an individual
  • Death of another unit member
  • Injury resulting in the loss of a limb

Operational Stressors

  • Prolonged exposure to extreme geographic environments such as desert heat or arctic cold
  • Reduced quality of life and communication resources over extended period of time
  • Prolonged separation from significant support systems, including family and friends
  • Cumulative exposure to significant injuries, such as witnessing the death of several unit members over the course of many combat missions

Common COSRs include:[ Reference 2 ]
  • Fatigue
  • Muscular tension
  • Shaking and tremors
  • Sleep disturbance
  • Visual and hearing problems and partial paralysis
  • Anxiety
  • Short attention span
  • Depression
  • Low energy level
  • Social withdrawal
  • Change in outward appearance
  • Substance abuse

Intervention for COSRs

According to the VA/DoD Clinical Practice Guideline for Management of Post-Traumatic Stress, symptoms will resolve rapidly with simple measures, such as reassurance, rest, and enduring safety.[ Reference 1 ]

However, if service members with COSRs do not respond to the initial interventions, they may be referred to a licensed mental health provider or evacuated if in theater.[ Reference 1 ]



  1. VA/DoD Evidence Based Practice Work Group. (2017). Management of Posttraumatic Stress Disorder and Acute Stress Reaction 2017 Full Guideline. Retrieved from

  2. Department of the Army. (March, 2009). FM 6-22.5 Combat and operational stress control manual for leaders and soldiers. Washington, DC: Headquarters Department of the Army.