Pain: what is going on?

Pain is a way for the brain to alert the body to potential danger. It can be experienced in many different ways, from mild discomfort to severe and constant pain. There are also many different treatments for managing pain.


What is pain?

Pain is a warning system for our bodies, letting us know that there is a risk of damage happening.

Pain is complex. It might be felt as mild discomfort, severe cramping, constant dull aches or short stabbing sensations.

Pain is also a personal experience. 

The same events can cause different kinds of pain for different people

Jane hurts her back picking something up from the floor

John hurts his back picking something up from the floor

Low back muscle is strained

Low back muscle is strained

Jane rubs area and returns to activity

John has to stop moving and rest for several hours

Pain is gone within hours

John has to take medicine to ease pain

Pain continues for days, or even weeks

The experience of pain is individual for many reasons that are not just physical – for instance, the type of injury or where the injury has happened.

Emotional health, for example, feeling low and depressed or excited and alert, can affect how someone feels pain.

Cultural and social expectations can also influence how a person experiences pain.

One thing we all have in common is that wherever the pain is in our bodies, our brains play an important role. The brain takes all the influences described above and mixes them together. The result is the type of pain each individual feels and also how each person responds to the pain. And that will be unique to each of us.

Even though the brain is important to the way we feel pain, that doesn’t mean pain is ‘all in your head’.

Pain is very real.

So what’s going on?

Pain as a protection system

Often, a person feels pain because they have been injured. The pain tells them that there is damage, and that they need to do something, such as fix the injury or move away from the cause of the damage.

The brain helps to make those decisions, based on information about what is happening to the person. This could be about the physical cause of the pain, how the person is feeling mentally and emotionally, and also how other people expect that person to react to pain.

After considering all this, the brain decides whether the body is in danger, whether the body needs protecting, and what needs to be done.

Usually the brain gets it right deciding what type and level of pain to feel, and what to do to protect the body from any further harm.

For example, a sprained ankle hurts to walk on, so limping or using crutches are appropriate responses. Touching a hot stove will cause a reflex that removes the body part quickly before too much damage can occur, and make the person more careful around the stove to avoid further injuries.

At other times, a decision is not straightforward. A person damages their back but feels leg pain (this is called referred pain) or someone has an arm or leg amputated, but still experiences pain there (this is called phantom limb pain).

Another example is chronic non-cancer pain. In this type of pain, changes to the nervous system make the brain overprotective and the body excessively sensitive to what is happening around it. This increased sensitivity interprets the information as pain.

Watch Professor Lorimer Mosely explain. 

Dr Moseley is Professor of Clinical Neuroscience, Chair in Physiotherapy, University of South Australia, Adelaide.

Types of pain

A common way to categorise pain is by the length of time a person has been feeling it.

Acute pain

Acute pain starts suddenly and tends to be short-lived. It can range from mild to severe and can have many different causes. Usually it happens as a normal response to damage. The term 'acute' does not mean the pain is severe but rather that it lasts for a few moments, days or weeks.

Acute pain is a warning that damage has occurred to your body, that you need to protect the damaged area, and seek help to address the cause. Acute pain usually reduces or goes away as the damage to your body heals.

Many different conditions, including injuries and diseases, can lead to acute pain.

The best way to treat acute pain will depend on what type of pain it is and what has caused it. Common treatments can be physical – such as staying active and using heat or cold to reduce the pain or taking medicines for the relief of short-term pain. Learning about the pain can also help a person to understand it better and may be a useful part of treatment.

For more information about management in general and specific treatments for acute pain, see Card 4: Managing pain.

Chronic pain

Chronic pain is pain that lasts more than 3 months or longer than expected for healing after surgery, injury or a condition. The cause may also be unknown. It is sometimes called 'persistent pain'.

Chronic pain can be caused by an ongoing condition, such as nerve pain or migraine, among others. 

Sometimes chronic pain occurs after a person has had acute pain, but the original cause of the acute pain no longer exists. This can be frustrating for the person experiencing the pain. It can also be challenging to treat the chronic pain that has now taken over.

Find out more about chronic pain

Pain conditions

Pain can be a symptom in many conditions. Correct diagnosis and management of pain varies for different pain conditions.

For more information about some of these conditions, including what they are and how they can be managed, see:

Managing pain

Living with pain, whether it is acute or chronic, can be challenging. There is no one-size-fits-all approach to the management of pain.

Different treatments may be recommended by medical experts. These treatments may include:

  • simple treatments: such as learning about your pain, physical activity that is gradually increased, and self-management such as using a heat or cold pack
  • physical treatments: such as massage and mobilisation
  • psychological treatments: such as cognitive behavioural therapy (CBT) or cognitive behavioural-based interventions, hypnosis, relaxation, meditation, mindfulness, acceptance and commitment therapies, psychoanalytic and psychodynamic therapies.
  • pain medicines: such as paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs) and if required, opioids
  • invasive procedures: such as nerve blocks (a pain reliever medicine injected towards a nerve), radiofrequency neurotomy (use of heat to temporarily turn off a nerve’s ability to send pain signals).

Which treatments are best?

In general, treating the cause of the pain is best wherever possible. If pain itself is the target of management, treatments other than invasive procedures can be tried first to provide pain relief.

In many cases, pain relief is best achieved with a combination of treatments. For example, if someone has acute low back pain (and the cause is not a serious condition such as infection or cancer), medical experts recommend starting with a combination of:

  • learning about the nature of low back pain
  • reassurance that many people recover rapidly
  • self-managing the symptoms, such as by putting a heat pack on the painful area, and
  • staying active and avoiding bed rest.

Find out more about low back pain

For chronic pain not related to cancer, medical experts recommend similar treatments to those for low back pain. They also add:

  • psychological and mind-body treatments that address underlying thoughts, feelings, emotions and behaviours about pain,
  • mindfulness and relaxation, and
  • medicines such as paracetamol and NSAIDs.

If someone feels pain for longer than expected, or if different treatments have been tried but are not really helping, they should talk to a health professional.

Find out more about chronic pain

Medicines for pain

As well as treating the cause of the pain if there is one (for example a broken bone), many people will also take some kind of pain reliever medicine.

What is a pain reliever?

Pain relievers are medicines that work on the body's nervous system to reduce the feeling of pain. They are also known as analgesics and pain relief medicines. People also use the term ‘pain killer’, but this is not accurate and can set up unrealistic expectations about a medicine.

Pain relievers have different active ingredients. It's important to know what these are and which one(s) you are taking, particularly if you are taking more than one medicine.

Many pain relievers can be bought over the counter without prescription. These include paracetamol, and non-steroidal anti-inflammatory medicines (NSAIDs) such as ibuprofen, aspirin and diclofenac (eg, Voltaren).

Find out more about active ingredients

Find out more about pain relief medicines

4 facts about pain relievers

  1. They provide temporary pain relief – they do not treat the cause of the pain.
  2. Some types of pain respond better to particular pain relief medicines than to others.
  3. Each person may have a slightly different response to a particular pain reliever.
  4. Pain medicines have risks as well as benefits, so it's worth knowing how to use them

Which pain relief medicine?

Talk to your doctor or pharmacist about all the medicines you are currently taking so they can advise you which pain relievers are best for you, and how to take them safely. Make sure you include all pain relievers, both prescription and non-prescription, on a medicines list.

You can find out more about your pain medicine by reading the consumer medicine information (CMI). Search for the CMI for your medicine in our Medicine Finder.

Did you know?

Overuse of a pain-reliever medicine can produce a 'medication-overuse headache'. How much use is overuse? It usually means when medicines are taken for more than 10–15 days a month for a number of months.