Everyone feels anxious and has a sense of panic from time to time. It’s part of an automatic response called ‘flight or fight’ which is designed to help us respond to sudden dangers or threats. We’ve all had that moment of panic when we can’t answer a question in an exam, or a car doesn’t stop when we’re crossing the road.

The response evolved millions of years ago when early humans often met life-threatening situations. When suddenly faced with a saber-toothed tiger, we needed to react quickly by either running away or fighting.

We no longer need to deal with the threat posed by wild animals but we can experience the same response today in situations we fear or find stressful. A job interview, walking through a crowded shop, or, running late for an important deadline, for example. The response is triggered as soon as the brain becomes aware of a possible danger. Hormones, called adrenaline and cortisol, are quickly released to help the body prepare for running away or fighting. These changes include:

  • our breathing getting quicker and heavier to take in extra oxygen
  • the heart beating faster to send blood to the leg muscles
  • muscles all over the body tensing and legs shaking to get ready to run
  • feeling ‘butterflies’ in the stomach as blood is diverted from the digestive system

Watch our Flight or fight animation to learn more about anxiety and the threat response.

Read transcript of The flight or fight response animation

Download our Flight or fight diagram as a pdf:

In a panic attack the ‘flight or fight’ response, which is very sensitive to possible danger, is triggered when someone feels frightened or under attack. This can happen even though there may not be an immediate danger in reality. Panic attacks are often described as a ‘fire alarm sounding when there’s no smoke or fire.’

The physical symptoms of the ‘flight or fight’ response are felt much more intensely than usual and can build up very quickly. They may include:

  • breathing much faster
  • fast-beating heart (palpitations)
  • shaking or wobbly limbs
  • chest pain
  • upset stomach – feeling sick or having to rush to the toilet
  • sweating and hot flushes
  • feeling faint or dizzy
  • dry mouth
  • stiff muscles
  • difficulty concentrating
  • feeling numb or frozen and unable to feel emotion

Some people also report feeling detached from their body like they are watching themselves from a distance (known as Depersonalisation) or feeling things or people around them are unreal or unfamiliar, known (known as Derealisation).

In reality, the panic attack itself is not dangerous. Once the feeling of intense anxiety starts to ease your heart rate will start to slow down, your breathing will become more regular and your body can quite quickly get back to normal.