PTSD and Trauma-Related Disorders

Necessary cause — the Criterion A event

• Qualifying trauma exposure: actual or threatened death, serious injury, or sexual violence, experienced directly, witnessed, learned of in a close relative/friend (violent or accidental), or through repeated occupational exposure to aversive details (first responders, forensic investigators). Media exposure alone does not qualify unless work-related.
• Conditional risk varies by trauma type: interpersonal and intentional trauma (sexual assault, torture, captivity, combat) produces far higher rates of PTSD than impersonal trauma (natural disaster, motor vehicle collision) — the perceived intentionality and betrayal amplify fear conditioning.

Pretraumatic, non-modifiable

• Female sex: roughly twice the lifetime prevalence of men, partly reflecting higher exposure to sexual violence.
• Prior psychiatric history and childhood adversity: preexisting depression/anxiety, prior trauma, and childhood abuse or neglect sensitize the HPA axis and amygdala-prefrontal circuit described above.
• Family history/genetics and lower cognitive reserve: heritability is modest; lower education, lower IQ, and lower socioeconomic status recur in exam stems.

Peritraumatic (event-related)

• Trauma severity, injury, and perceived life threat: the subjective sense of imminent death predicts PTSD better than objective injury severity.
• Peritraumatic dissociation: derealization or "watching myself from outside" during the event is one of the strongest single predictors — a favorite planted detail.

Posttraumatic, modifiable — where intervention matters

• Poor social support after the event: the most consistently modifiable predictor of chronicity.
• Avoidant coping and substance use: alcohol/opioid self-medication blocks extinction learning and worsens prognosis.
• Early benzodiazepine exposure: associated with worse outcomes, not prevention.
• Subsequent life stressors, chronic pain, and comorbid TBI: sustain arousal and impede recovery.
• Untreated acute stress disorder: early trauma-focused CBT reduces progression to PTSD (VA/DoD Clinical Practice Guideline for PTSD/ASD).

Neurobiological Alterations in PTSD

• Amygdala hyperactivity: The amygdala (fear/threat detection center) becomes hyperresponsive to trauma-related cues and even neutral stimuli, leading to exaggerated fear conditioning and persistent threat perception; this is the neurobiological basis for hyperarousal and heightened startle response
• Prefrontal cortex (PFC) hypoactivity: Reduced function in the medial prefrontal cortex (critical for fear extinction and emotional regulation) impairs the ability to suppress conditioned fear responses and contextualize trauma memories; this explains poor extinction learning and difficulty with cognitive reappraisal
• Hippocampal dysfunction: Decreased hippocampal volume and reduced activation impairs explicit memory processing and contextualization of traumatic memories, resulting in fragmented trauma memories that are stored non-verbally (explaining why sensory triggers can provoke flashbacks without conscious recall)
• Altered HPA axis regulation: Trauma produces dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, characterized by paradoxically LOW cortisol levels (unlike acute stress) and enhanced negative feedback sensitivity, contributing to sustained hypervigilance despite inadequate stress hormone levels
• Noradrenergic system hyperactivity: Chronic elevation of norepinephrine in the locus coeruleus increases arousal, anxiety, and startle reactivity; this explains why α2-adrenergic agonists (prazosin) can be therapeutic for hyperarousal symptoms
• Glutamate excitotoxicity: Excessive glutamatergic neurotransmission in fear-related circuits promotes maladaptive learning and maintenance of traumatic memories
• Epigenetic modifications: Trauma can cause DNA methylation changes and histone modifications in genes regulating stress response, potentially contributing to intergenerational transmission of trauma vulnerability

Core Symptom Clusters (DSM-5 Criteria)

• Intrusion symptoms (at least 1 required): Recurrent, involuntary, distressing memories of the trauma; nightmares related to the event; flashbacks with dissociative features where the person feels as if the trauma is happening again; intense psychological distress upon exposure to reminders; marked physiologic reactivity to trauma cues (e.g., panic response to sounds resembling gunfire in combat veterans)
• Avoidance symptoms (at least 1 required): Avoidance of trauma-related thoughts or feelings; avoidance of external reminders (people, places, activities, objects, situations) that trigger distress; progressive avoidance that expands beyond the original trauma context
• Negative alterations in cognition and mood (at least 2 required): Inability to recall important aspects of the trauma (dissociative amnesia—NOT due to head injury); persistent, distorted negative beliefs about self ("I am bad," "I deserve this"), others ("people cannot be trusted"), or the world ("the world is completely dangerous"); persistent blame of self or others for the trauma; pervasive negative emotional state; markedly diminished interest or participation in significant activities (anhedonia); feeling detached or estranged from others; persistent inability to experience positive emotions (emotional numbing)
• Alterations in arousal and reactivity (at least 2 required): Hypervigilance and exaggerated startle response; reckless or self-destructive behavior; hyperactivity or difficulty concentrating; sleep disturbance (insomnia, nightmares); irritability or aggressive behavior often triggered by perceived threats

Important Clinical Presentations and Variants

• Combat PTSD: Characterized by intense hypervigilance, "combat readiness," hyperaggression, and difficulty adjusting to civilian safety; veterans may describe being "on alert" even in secure environments
• Sexual assault/abuse PTSD: Often includes prominent shame, guilt, self-blame, sexual dysfunction, and difficulty with trust; higher rates of comorbid depression and suicidality
• Childhood trauma PTSD: May present with developmental delays, behavioral problems, difficulty with emotional regulation, and dissociative symptoms; often includes complex PTSD features
• Motor vehicle accident PTSD: Specific avoidance of driving or riding in vehicles; anxiety triggered by traffic sounds or road conditions
• Flashbacks with dissociation: Patients may experience dissociative flashbacks (severe form) where they lose awareness of present time/place and fully relive the trauma with complete sensory reproduction
• Trauma-related nightmares: May be exact replays of the trauma or thematically related; often disrupt sleep and contribute to chronic sleep deprivation
• Trigger-induced panic attacks: Unlike primary panic disorder, these are specifically tied to trauma reminders and occur in a more predictable context

Clinical Pearls

• PTSD requires that symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning—transient stress responses do not meet criteria
• The one-month duration threshold is crucial—symptoms lasting less than one month constitute acute stress disorder instead
• Approximately 50% of PTSD patients have comorbid major depression; always screen for depression and suicidality
• High rates of comorbid substance use disorder (patients self-medicate with alcohol or drugs); PTSD patients with SUD have worse prognosis
• Anger and aggression are frequently underrecognized PTSD symptoms, particularly in male veterans and trauma survivors; irritability may be the primary mood disturbance rather than depression

Diagnostic Criteria and Approach

• DSM-5 Criteria (gold standard): PTSD diagnosis requires (1) exposure to a qualifying traumatic event, (2) at least 1 intrusion symptom, (3) at least 1 avoidance symptom, (4) at least 2 negative cognition/mood symptoms, (5) at least 2 arousal/reactivity symptoms, (6) duration ≥1 month, (7) functional impairment, and (8) symptoms not attributable to substance use or medical conditions; notably, the DSM-5 removed the requirement for guilt/shame as these are subsumed in negative cognition symptoms
• Clinical interview and history: Obtain detailed trauma history including type of trauma, timing, severity, and perception of threat/injury; assess current symptoms mapped to DSM-5 clusters; evaluate for dissociative features and distinguish PTSD flashbacks from psychotic symptoms or other conditions; assess suicide risk (elevated in PTSD); screen for substance use as both cause and consequence
• Structured diagnostic instruments: PTSD Checklist for DSM-5 (PCL-5) is a 20-item self-report screening tool with excellent sensitivity/specificity; Clinician-Administered PTSD Scale (CAPS-5) is the gold standard clinician-administered assessment tool (more time-intensive); useful for diagnostic confirmation and symptom tracking
• Differential diagnosis considerations: Distinguish from acute stress disorder (symptoms 3 days–1 month), adjustment disorder (response to identifiable stressor that does not meet full PTSD criteria), major depressive disorder (PTSD has trauma-specific features and intrusion/avoidance), generalized anxiety disorder (GAD lacks trauma history and specific trauma-related content), panic disorder (panic attacks in PTSD are cue-specific), obsessive-compulsive disorder (OCD obsessions are not trauma-specific), and psychotic disorders (PTSD flashbacks retain reality testing, unlike hallucinations)
• Physical examination and labs: No specific diagnostic tests; perform general medical evaluation to rule out medical causes (traumatic brain injury, chronic pain conditions); assess for substance use via screening or urine drug screen; consider baseline blood pressure and heart rate given sympathetic hyperactivity
• Neuroimaging: NOT

Immediate stabilization

• Safety first: assess suicidal ideation, access to firearms (especially in veterans), homicidality/aggression, and intoxication or withdrawal before anything else; acute suicidality warrants emergency evaluation and possible hospitalization.
• Acute trauma (first days to weeks): supportive care, restoration of safety and social connection. Single-session psychological debriefing (CISD) is not recommended — it does not prevent PTSD and may worsen outcomes.

First-line therapy — psychotherapy preferred

• Trauma-focused psychotherapy: both the VA/DoD Clinical Practice Guideline and the APA Clinical Practice Guideline for PTSD recommend individual, manualized trauma-focused therapy over medication as initial treatment. Representative modalities: prolonged exposure (extinction learning that recruits the hypoactive medial PFC), cognitive processing therapy (restructures distorted trauma appraisals), and EMDR.
• Pharmacotherapy when psychotherapy is unavailable, declined, or insufficient: SSRIs — sertraline and paroxetine are the only FDA-approved agents — or the SNRI venlafaxine. Allow an adequate trial of several weeks at therapeutic dose before declaring failure.

Symptom-targeted and second-line

• Prazosin (α1-antagonist): blunts CNS noradrenergic signaling and is classically tested for trauma-related nightmares; titrate slowly because of first-dose orthostatic hypotension.
• Escalation: switch within or across class (SSRI → different SSRI or SNRI), or combine medication with trauma-focused therapy.
• Adjunctive care: treat comorbid depression, alcohol/substance use disorder, and insomnia; CBT-I for residual insomnia.

Avoid / contraindicated

• Benzodiazepines: VA/DoD recommends against them — they impair fear extinction, worsen long-term outcomes, and add dependence and respiratory-depression risk with opioids.
• Atypical antipsychotics as monotherapy and routine adjunctive risperidone are not recommended.
• Cannabis and alcohol as self-treatment worsen course.

Disease-related

• Suicide — emergency: PTSD independently raises suicide risk, amplified by comorbid depression, alcohol use, and firearm access. Signalled by new hopelessness, giving away possessions, or escalating reckless behavior; requires immediate risk assessment and means restriction.
• Comorbid major depression and substance use disorder: shared HPA/monoamine dysregulation plus self-medication of hyperarousal. Alcohol withdrawal in a hospitalized PTSD patient can progress to delirium tremens — a medical emergency.
• Aggression and interpersonal/occupational collapse: amygdala-driven threat misappraisal with weak prefrontal inhibition; manifests as job loss, divorce, legal trouble, and homelessness.
• Chronic insomnia and nightmares: sustained sleep fragmentation impairs extinction consolidation, creating a self-perpetuating loop.
• Somatic morbidity: chronic sympathetic and inflammatory activation is associated with hypertension, cardiovascular disease, chronic pain, and metabolic syndrome.
• Dissociative subtype/derealization: prolonged dissociative episodes can be mistaken for psychosis or seizure; reality testing is retained between episodes.

Treatment-related

• SSRIs/SNRIs: sexual dysfunction (the leading cause of nonadherence), GI upset, SIADH with hyponatremia in older adults (confusion, seizures — emergency if severe), increased bleeding risk with NSAIDs/antiplatelets, and the FDA boxed warning for suicidality in patients under 25 during initiation.
• Serotonin syndrome — emergency: clonus, hyperreflexia, agitation, hyperthermia and autonomic instability when an SSRI/SNRI is combined with triptans, linezolid, tramadol, or MAOIs.
• Discontinuation syndrome: abrupt stoppage of paroxetine or venlafaxine (short half-lives) causes flu-like symptoms, dizziness, and "brain zaps"; taper instead.
• Prazosin: first-dose syncope and orthostatic hypotension, especially with volume depletion or other antihypertensives.
• Benzodiazepines: tolerance, dependence, cognitive impairment, falls, blunted therapeutic extinction learning, and fatal respiratory depression with opioids.
• Exposure therapy: transient symptom exacerbation early in treatment — expected, not a reason to stop unless the patient destabilizes.

• The clock is the diagnosis: <3 days = normal acute stress reaction; 3 days–1 month = acute stress disorder; >1 month = PTSD. Symptoms may have delayed expression (full criteria met ≥6 months after the event) — a late-onset stem is still PTSD, not malingering.
• Single best next step in a stable patient: refer for trauma-focused psychotherapy (prolonged exposure, cognitive processing therapy, or EMDR) — VA/DoD and APA both favor it over drugs as initial treatment. Medication is the answer when the stem says therapy is refused or unavailable.
• The drug association examiners test: sertraline and paroxetine are the only FDA-approved agents for PTSD; venlafaxine is the SNRI alternative.
• Prazosin for trauma-related nightmares: the α1-blocker link to noradrenergic hyperactivity is the classic testable mechanism. Watch for first-dose orthostasis.
• The commonest distractor: benzodiazepines. Never the right answer in PTSD — they impair extinction learning, worsen long-term outcomes, and add dependence. Similarly, single-session critical incident debriefing immediately after trauma is a trap: it does not prevent PTSD.
• Flashbacks retain reality testing and are cue-triggered; auditory hallucinations with loss of insight point to a primary psychotic disorder instead.
• The counterintuitive lab finding: cortisol is low, not high, in chronic PTSD despite hypervigilance — enhanced glucocorticoid negative feedback, opposite the pattern in major depression.
• Always screen for suicide, alcohol/substance use, and depression — roughly half have comorbid major depression, and firearm access in a veteran with active ideation makes means restriction the immediate next step.
• Adjustment disorder is the answer when the stressor is real but sub-Criterion A (job loss, divorce) and the full symptom clusters are absent.