PTSD

PTSD Symptoms: The Four Types and How to Recognise Them

By Jess, Mental Health Writer 12 July 2026 7 min read

Post-traumatic stress disorder (PTSD) can develop after experiencing or witnessing a traumatic event. It’s a recognised, treatable condition — not a sign of weakness — and understanding its symptoms is the first step toward getting help. PTSD symptoms fall into four groups.

1. Intrusion (re-experiencing)

The trauma pushes its way back into the present:

  • Intrusive, unwanted memories of the event
  • Nightmares or distressing dreams
  • Flashbacks — feeling as though the event is happening again
  • Intense distress or physical reactions when reminded of it

2. Avoidance

Understandably, you try to keep the trauma at bay:

  • Avoiding thoughts, feelings or conversations about the event
  • Staying away from people, places or situations that trigger memories

3. Negative changes in mood and thinking

  • Persistent negative beliefs about yourself or the world
  • Ongoing fear, guilt, shame or anger
  • Feeling detached or estranged from others
  • Losing interest in activities; difficulty feeling positive emotions
  • Gaps in memory of the traumatic event

4. Hyperarousal (being “on guard”)

  • Being easily startled or constantly on alert
  • Irritability or angry outbursts
  • Difficulty sleeping or concentrating
  • Reckless or self-destructive behaviour

When symptoms become PTSD

It’s normal to have some of these reactions after trauma. They’re considered PTSD when they persist for more than a month, cause significant distress, and interfere with daily life. When trauma is prolonged or repeated — such as childhood abuse or ongoing violence — it can lead to complex PTSD, which has additional features.

Getting help

PTSD responds well to trauma-focused treatment, and you don’t have to manage it alone. You can start with our free, confidential PTSD self-check, read about PTSD treatment options, or learn about the PTSD care we provide. A psychiatrist can assess your symptoms and build a treatment plan — book an appointment with a GP referral.

This article is general information, not medical advice. If you’re struggling, please speak with your GP. In a crisis, call Lifeline on 13 11 14 or 000.

Jess — Mental Health Writer

Jess is a mental health writer at Psychiatrists Australia, creating clear, compassionate content to help people understand mental health conditions and navigate their care options.

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