# Acute Stress Reaction

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**Course:** [Mental Health: UKMLA](https://medexcellence.co.uk/courses/mental-health)  
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Transient psychological response to extreme stressors; resolves within weeks. Becomes PTSD if symptoms persist >1 month.

Acute Stress Reaction     Definition   • Acute Stress Reaction (ASR) is a transient psychological response to an extreme stressor or traumatic event (e.g., accident, assault, natural disaster). • It occurs within minutes to hours of the event and typically resolves within days to a few weeks. • If symptoms persist >1 month, it may progress to Post-Traumatic Stress Disorder (PTSD).    Pathophysiology   • Exposure to a traumatic stressor triggers an acute fight-or-flight response, mediated by the hypothalamic-pituitary-adrenal (HPA) axis. • Dysregulation of stress hormones (cortisol, adrenaline) leads to emotional, cognitive, and physical symptoms.    Common Causes of Acute Stress Reaction    Physical Trauma  – Accidents, Assault, Physical Abuse, Natural Disasters   Psychological Trauma  – Sudden Bereavement, Witnessing Death or Injury   Combat or Emergency Situations  – Military Combat, First Responders, Hostage Situations   Serious Illness or Diagnosis  – New Terminal Illness, Severe Injury    Risk Factors for Acute Stress Reaction    Previous Trauma or PTSD  – Higher Risk of Severe Reaction   Personal or Family History of Anxiety or Depression  – Pre-existing Mental Health Disorders   Lack of Social Support  – Increases Vulnerability to Psychological Distress   Neurotic Personality Traits  – Greater Emotional Reactivity to Stressors    Key Point  Severe trauma and pre-existing mental health conditions increase the risk of ASR.    Symptoms of Acute Stress Reaction    Emotional Symptoms  – Anxiety, Fear, Helplessness, Guilt, Irritability   Cognitive Symptoms  – Difficulty Concentrating, Disorientation, Intrusive Thoughts   Dissociative Symptoms  – Detachment, Emotional Numbing, Amnesia   Physical Symptoms  – Palpitations, Sweating, Hyperventilation, Tremors   Behavioural Symptoms  – Avoidance of Reminders, Restlessness, Hypervigilance    Signs on Examination    Agitation & Restlessness  – Hyperalertness, Increased Startle Response   Emotional Distress  – Crying, Irritability, Fearfulness   Tachycardia & Hypertension  – Autonomic Activation   Hyperventilation & Sweating  – Physical Manifestation of Anxiety    Clinical Insight  Dissociation, intrusive thoughts, and autonomic symptoms are hallmarks of ASR.    Referral Criteria (NICE Guidelines)    Urgent Referral   • Suicidal Ideation or Self-Harm Risk • Severe Functional Impairment (Unable to Perform Daily Activities) • Violent or Aggressive Behaviour    Routine Referral   • Ongoing Flashbacks, Hypervigilance, or Emotional Numbing • Avoidance Behaviour Leading to Social Isolation • Significant Sleep Disturbances    Important  Persistent symptoms (>4 weeks) suggest PTSD and warrant referral for psychological support.    Clinical Diagnosis (ICD-10 / DSM-5)    Exposure to Severe Stressor  – Directly Experiencing or Witnessing Trauma   Immediate Emotional Reaction  – Fear, Helplessness, or Horror   Dissociative Symptoms  – Detachment, Depersonalisation, Derealisation   Re-Experiencing Symptoms  – Flashbacks, Intrusive Thoughts, Nightmares   Hyperarousal Symptoms  – Insomnia, Irritability, Exaggerated Startle Response   Duration <4 Weeks  – If >1 Month, Consider PTSD    Differential Diagnosis    Panic Attack  – Sudden, Short-Lived (Minutes to Hours), No Trauma Preceding   Post-Traumatic Stress Disorder (PTSD)  – Symptoms Persist >1 Month, Flashbacks & Hyperarousal   Generalised Anxiety Disorder (GAD)  – Chronic Worry, No Specific Triggering Event   Depression  – Low Mood & Anhedonia Without Acute Hyperarousal    Clinical Insight  Diagnosis is clinical; PTSD should be considered if symptoms persist.    Management (NICE Guidelines)    Immediate Psychological First Aid (First-Line)    Calm & Supportive Environment  – Reduce Sensory Overload, Offer Reassurance   Encourage Social Support  – Friends, Family, Community Networks   Grounding Techniques  – Breathing Exercises, Reorienting to Present   Psychoeducation  – Explain Normal Stress Reactions & Coping Strategies    Short-Term Symptom Management    Insomnia  – Short-Term Zopiclone or Promethazine (Avoid Benzodiazepines)   Anxiety & Hyperarousal  – Beta-Blockers (Propranolol) for Autonomic Symptoms   Emotional Distress  – Short-Term Psychological Support (CBT If Persistent)    When to Consider Psychological Therapy   • If Symptoms Persist >4 Weeks (Risk of PTSD) • If Symptoms Are Severe or Affecting Daily Life    Management Insight  Most cases resolve with psychological support; medications should be avoided unless symptoms are severe.    Prognosis    Mild ASR (Most Cases)  – Resolves Within Days to Weeks   Severe ASR  – Higher Risk of PTSD    Complications    Post-Traumatic Stress Disorder (PTSD)  – Persistent Flashbacks, Avoidance, Hyperarousal (>1 Month)   Depression  – Chronic Low Mood, Social Withdrawal   Substance Abuse  – Self-Medication with Alcohol or Drugs    Exam Insight  Early psychological intervention reduces the risk of PTSD.    UKMLA Key Points   • Best initial management: Psychological First Aid (Supportive Environment, Reassurance) • Best long-term management: Cognitive Behavioural Therapy (CBT) • Suspect PTSD if symptoms >1 Month with flashbacks and avoidance • Urgent referral: Suicidal ideation, violent behaviour, severe impairment • Pharmacology: Beta-blockers if needed, avoid benzodiazepines

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