What is pain?

Sometimes pain is really helpful because it warns you that something is wrong. At other times, it appears to serve no useful purpose.

On this page, you can find the following information:

Key points about pain

  1. There are 3 main types of pain: acute (sudden and short term), chronic (ongoing) and intermittent (it comes and goes).
  2. With acute pain, a signal travels through nerve fibres to your brain. You then feel the pain, which lets you know something is wrong, such as a sprained ankle.
  3. Chronic pain or long-term pain is pain that lasts for months or years. It appears to serve no useful purpose and can be difficult to live with.
  4. Intermittent pain comes and goes such as headache.
  5. The experience of pain is different for each person, and so there are various ways to feel and describe it.
  6. Treatment for pain depends may be a medicine or non-medicine treatment, depending on the type of pain, what has caused it and where it is.

What is pain?

The International Association for the Study of Pain defines pain as “An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage.”

This means pain is an uncomfortable feeling that tells you something may be wrong in a part of your body. It’s the result of a message from special nerves (called nociceptors). When they find damaged tissue in your body, the send information about the damage along your spinal cord to your brain. 

For example, if you touch a hot surface, your body causes an instant reflex that pulls your hand away before you do any more damage. But even if you’ve pulled your hand away, the nociceptor nerves still send a message to your brain that some tissue has been damaged. Once that message gets to your brain, you start to feel an unpleasant sensation – pain. This means you can then do something about, in the case, the burn. 

This is a complex system and it works well for acute pain. Sometimes this system can go wrong. The messages get confused and your brain can’t understand the signals properly.

This can lead to chronic or persistent pain, which can be very hard to repair. Unfortunately, you can’t just re-boot the system when it goes wrong, the way you can with a computer system.

So while pain has a helpful role to play, it can also have negative effects on your functioning and social and psychological wellbeing.
(Central London Community Healthcare NHS Trust, UK, 2012)

Why do people experience pain differently?

We all experience pain in our own way. We learn about pain through life experiences. This means how we think and feel about pain is shaped by how our parents talked about pain, and other attitudes and beliefs about pain we have picked up along the way. For example, men are often taught to ignore the physical signs of pain more than women are. 

Another factor that affects how you feel pain is because it is a whole body experience. The pain signals use your spinal cord and specialised nerve fibres to travel to your brain. 

This links with the emotional centres in your brain. This means how you are feeling has an effect on your pain. If you feel angry, depressed or anxious, your pain can seem worse. If you are feeling positive and happy, your pain can seem to be less, and you are able to cope better. 

It shows that pain is never “all in your mind” or “just in your body”. It’s a complex mix involving your whole being and how your brain interprets the signals. You know your pain, even though it can't be seen. The challenge for you and those treating you is to understand the complicated nature of long-term pain and the best way to manage it.
(Ted-Ed, US, 2014)

What are the types of pain?

Pain is broken down into 3 main types: acute, chronic and intermittent. 

Acute pain usually comes on suddenly and is caused by something specific such as a burn or cut, bee sting, infection, broken bone, surgery, dental work or childbirth. 

Chronic or persistent pain is pain that lasts longer than 3 months. It is also called persistent pain or long-term pain. It is often described as pain that does not go away as expected after an illness or injury. It’s a much more complex type of pain, where the brain is still sending pain signals but your body has healed. 

Intermittent pain is pain that comes and goes, such as a headache. 

What causes pain? 

Often the cause of acute pain is obvious, such as a broken leg or a bruise. Sometimes the source of pain is unseen, eg, a slipped disc. Sometimes pain is a sign of a serious condition.

Occasionally it is very difficult to find the exact cause of a person’s pain. 

Where the pain appears in your body is a clue to what might be causing it. Use this guide to help work out what might be the problem: Pain location

Pain can be steady, throbbing, stabbing, aching, pinching, or described in many other ways.

Describing your pain accurately can help your doctor make the right diagnosis and develop the best treatment plan for you. It's fine to describe things in your own words – you don't need to use medical terms. Here’s some ideas of how you can do that: Describing your pain 

Your report of an experience as pain should be respected, and if you don’t feel your healthcare provider is doing that, find someone who does.

How does chronic pain develop?

Sometimes, pain can begin very small. But the signals quickly jump along the pain network described above. It is like a football crowd. It takes only one person to start a chant or a song, but very quickly the whole stand has joined in. 

This is called ‘wind- up’. It is one of the reasons why chronic pain does not go away easily. The ‘chant’ can last for hours, days or even years. This can lead to a long-term, distressing problem that requires skill, time and patience to improve. 

The way a pain signal jumps along the system is by the release of a chemical. These are called neurotransmitters. There are good neurotransmitters and there are bad neurotransmitters. The bad ones make the pain worse; the good ones can help block the pain. 

Again, the way you feel is involved in this process. By doing something you enjoy, such as having a good laugh or exercising, you can strengthen your good neurotransmitters and so limit your pain. 

However, if you are depressed or moody, lack motivation and are not active, you strengthen your bad neurotransmitters and your pain gets worse. You can then get caught in a chronic pain cycle. The good news is there are lots of points in the cycle where you can change this. Rad more about chronic pain. 

See this video for more information:

(Brainman, US, 2014)

How is pain treated?

The treatment for pain may involves medicine or a range of non-medicine treatments.


The choice of pain relief medicine depends on many things, such as the type, severity and cause of your pain, other medications you may already be taking, any allergies you may have and other conditions you may have.

Common pain relief medicines are paracetamol, non-steroidal anti-inflammatories (NSAIDs), COX-2 inhibitors, opioids, steroids, antidepressants and gabapentinoids. Read more about medicines for pain

Non-medicine treatments 

There is a range of non-medicine-based ways to help manage your pain. These include good self-care and exercise, as well as several types of treatment for your body and support for your mind. 

These include:

  • taking charge of the things you can change
  • physiotherapy
  • manual therapy
  • transcutaneous electrical nerve stimulation (TENS)
  • acupuncture
  • rongoā Māori
  • cognitive behavioural therapy (CBT)

Read more about non-medicine treatments for pain.


  1. What is pain? British Pain Society, UK
  2. What is pain, and how do you treat it? Medical News Today, UK, 2020
  3. What is pain? Healthline, US, 2019
  4. Understanding and managing long-term pain The British Pain Society, UK, 2015
  5. Pain definition updated after 40 years MedPage Today
  6. What is pain? WebMD, 2020
  7. What is pain? Pain Australia 
  8. What is pain/types of pain treated? Johns Hopkins Medicine, US