Medically unexplained symptoms

This information is for anyone with physical symptoms without an obvious physical cause. It also explains what you can do to help yourself and what treatments are available.

We all have physical symptoms – painful or uncomfortable feelings in the body – at different times in our lives.

Usually they get better on their own, without any treatment. If they don't, we might ask a doctor about them. Usually a physical cause can be found - but sometimes it can't, even when blood tests and x-rays or scans have been done.

Symptoms like this are common. They can be called “medically unexplained symptoms”, because they are not due to a physical illness in the body. However, they can be explained, but to do this, we need to think about causes that are not just physical.

We hope this information will also be helpful if you are a relative, friend or carer of someone with such symptoms.


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The content in this leaflet is provided for general information only. It is not intended to, and does not, mount to advice which you should rely on. It is not in any way an alternative to specific advice.

You must therefore obtain the relevant professional or specialist advice before taking, or refraining from, any action based on the information in this leaflet.

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We have all sorts of aches, pains and odd sensations in our bodies. 

Most of the time we know that these are part of our everyday life, that they will go away on their own, and we ignore them. 

If these changes are more painful or uncomfortable, or unusual, we know they may be signs of an illness – and we call them symptoms. 
  • About 1 in 4 people who see their GP have such symptoms. 
  • In a neurological outpatient setting, it is 1 in 3 patients or more’ *
  • The tests for your symptoms are all normal - but you still have your symptoms.
  • An important part of getting better is understanding what the problem is – and neither you nor your doctor know.
  • It can feel as though other people think that your problems are imaginary, or that you are making them up.

The commonest ones include:

  • pains in the muscles or joints
  • back pain
  • headaches
  • tiredness
  • feeling faint
  • chest pain
  • heart palpitations
  • stomach problems - pain, feeling bloated, diarrhoea and constipation.

These aren’t the only medically unexplained symptoms.  Other problems include collapsing, fits, breathlessness, weakness, paralysis, numbness and tingling.

When something in our body doesn’t feel right, there usually is a bodily or 'physical' cause -  stomach problems may be due to an infection, or palpitations may be due to a heart problem.

What if there is no physical explanation for your physical symptoms?  We can often understand and explain such symptoms when we look at how our thoughts, feelings and stresses can affect our bodies.

But – to say that a bodily symptom is not just physical is not the same as saying they are all in the mind. 

Medically unexplained symptoms aren't “all in the mind”, but neither are they all in the body. 

To understand them we have to think about how the mind and the body work together. 

We often think of our minds and bodies as two separate things.  In fact, they work together and affect each other.

Research shows that there is two way communication between our brains and bodies. This happens because:  

  • Signals travel down the nerves from the brain to the body ... and back again from the body to the brain.
  • Natural chemicals, called 'hormones', circulate in the bloodstream.  Some are produced by the brain and affect the body  ….. and some are made in the body and affect the brain and the way we feel.

Every day, thoughts, feelings and stresses play a part in making changes in our bodies - for example:

  • when we feel embarrassed, we blush
  • feeling worried or frightened can cause an uncomfortable feeling of "butterflies in the stomach"
  • when we get upset we feel our throat tighten – “a lump in the throat”.

We also know that the way we think and feel can make us physically ill.  For example:

  • feeling low or stressed makes any pain we have feel worse
  • long-term stress can make us more likely to have high blood pressure or a heart attack.

A disease in the body can affect the way we think and feel. 

There are different ways of thinking about how the mind and the body are linked that can help us to understand medically unexplained symptoms.

Like a computer – hardware and software

You can think of the brain and nerves as like the computer that sits on a desk. But the electrical messages that run through the nervous system are like computer programmes or ‘software’.

Let's look at what can happen when someone loses the use of an arm or a leg. It can be problem with the hardware.

The brain or nerves can be damaged by a stroke or an injury, so the messages can't get to or from the arms and legs. However, you can get the same symptoms without any damage to the brain and the nerves.

There seems to be a software problem. The brain and the nerves are intact but, because the software is not running properly, they are not controlling the limbs properly.

These ‘software’ problems can happen when you are under a lot of stress. Stress seems to interfere with messaging (or ‘software’) of the brain and nerves. A simple example is when someone collapses or faints when they are under stress, like a computer ‘crashing’.

Chronic pain can be like this. There doesn't seem to be physical damage that would cause pain, but something has gone wrong with the ‘software’ so that the brain is still getting pain messages.

Being ‘out of tune’

Another similar way of thinking about the cause of symptoms is like a car or piano being out of tune. All of the parts are there, but they aren’t working properly.

Over thousands of years, we have evolved a way of responding to stress that gets our body ready for physical action.  This was useful when life was more dangerous.  If a cave man (or woman) was attacked by a tiger, it was important that they were able to fight the tiger or run away.  This is sometimes called the “fight or flight response”.

How does this work? 

Our mind recognises the danger. The brain then sends signals to the body via the nerves and chemicals in the blood stream, particularly adrenaline. 

These signals get the body ready for action.  We breathe more quickly to get more oxygen into our blood stream. 

Our heart pumps faster and harder to get blood to our muscles. Our muscles become tense so that they are ready for action.

We still have lots of stresses

Nowadays, though, we don't need to physically react to most of these stresses.  For example, we may feel under stress if we take an exam, give a talk to colleagues at work, or if we need to be somewhere in hurry and our bus is late. 

Our body’s stress response gets going and our body gets ready for physical action - but there is nowhere for the energy to go.

This kind of stress response can give you:

  • rapid heartbeat and palpitations
  • chest tightness and breathlessness
  • dizziness, faintness and feeling light headed
  • feeling strange or “spaced out”
  • shakiness and tremor
  • indigestion, feeling sick, diarrhoea
  • dry mouth
  • tightness in the throat
  • numbness and tingling
  • headache, muscle tension and neck stiffness
  • sweating and feeling hot or cold.

These physical symptoms of stress can feel very uncomfortable, especially if we don’t know why they are happening.  They can make us feel ill. 

This worry can cause even more stress and bodily symptoms, making us feel even worse … and so on.  This is more likely to happen if stress goes on for a long time, as when we have money or job worries, or relationship problems.  

Chronic pain

We usually feel pain when there is damage to the body. However, we can feel long-term or chronic pain, even when there doesn’t seem to be a problem with the nerves. 

For example, pain can be caused by an injury, but chronic pain continues after the injury has healed.

It can be very frustrating to feel pain when there is no injury or bodily illness to account for it. We may be also be worried that people won’t believe how much pain we are in.

We think that chronic pain happens when intact nerves and areas of the brain that signal pain just seem to work wrong. (see the section above about “hardware and software”).

Pain can make us feel miserable and depressed, especially when it goes on for a long time. In turn, feeling depressed lowers our pain threshold and makes the pain feel worse. 

A vicious circle of pain and depression can occur where each makes the other worse.

It is natural to worry about our health when we have symptoms that we don’t understand.

 And some of us just worry more about our health than others.

This can make us more likely to have medically unexplained symptoms. This can happen for a number of reasons:

  • If family or friends have had serious illnesses, we may be concerned that we will become ill too.
  • We may carry our childhood experience of illness into our adult life.  For example, if our parents worried a lot about their (or our) health when we were children, we may be more likely to see a doctor about symptoms that someone else might ignore.
  • If we have already had an illness, this can make us more likely to notice ordinary feelings in our body and misinterpret them as signs of further illness. For example, someone who has had a heart attack may be on the look-out for symptoms that might suggest another heart problem.

Anxiety or depression obviously affect our mood, but they can also cause physical symptoms. We may recognise the physical symptoms, but find it harder to see that we are anxious or depressed. So we tend to think that these symptoms are due to a physical cause – when there is none. 

Most people who go to their GP with anxiety or depression begin by talking about bodily symptoms.


We have seen how the body’s stress reaction can cause a lot of bodily symptoms. When we are ill with anxiety, the body’s stress reaction is switched on when it is not needed. 

Some of the bodily symptoms that come with anxiety are described in the section above “How does feeling stressed cause physical symptoms?” 


When we are ill with depression, not only does it make us feel low or sad, but it also affects the body and causes symptoms such as:

  • loss of appetite
  • loss of weight
  • low energy
  • tiredness
  • general aches and pains.

It is common for people to have a physical illness, but also to have physical symptoms that are not fully explained by that illness. This can happen for a number of reasons.


A physical illness can causes emotional stress – which then creates physical symptoms of its own (see “How does feeling stressed cause physical symptoms?” above).

For example, someone with an illness such as asthma or emphysema can find it hard to breath at times. 

This can be frightening, which triggers the stress reaction described above.  This makes them breathe faster and their chest feels tight. 

A vicious circle is set up whereby breathlessness and stress each make each other worse. The breathlessness is then out of proportion to the illness that triggered it in the first place. 

Similarly, someone who is anxious about their heart may experience palpitations or chest tightness that are due to stress and not heart disease.


A painful physical illness can make us feel depressed.  This lowers our pain threshold and makes the experience of pain worse. 

A vicious circle can be set up, as described in the section on 'chronic pain' above.

Worries about our health

If we know that we have a physical illness we may be more alert for bodily symptoms that could indicate that our health is getting worse. 

We might find that sensations that we would otherwise ignore, such as aches or pains, become symptoms that we worry about.

We can give a name or a “diagnosis” for symptoms when:

  • they occur together in a particular pattern in many people, or
  • when they share a similar cause.

Diagnoses for certain patterns of medically unexplained symptoms include:

  • Irritable bowel syndrome – troubling stomach symptoms
  • Fibromyalgia –  widespread bodily pain and tenderness
  • Non-epileptic attack disorder – in epilepsy, fits are caused by problems with the electrical activity of the brain.  In non-epileptic attack disorder, someone has fits that look like epileptic fits, but the electrical activity of the brain is normal.

Examples of diagnoses that may be made because of possible causes of these symptoms include:

  • Somatisation disorder and somatoform disorder – where stress is thought to be a major cause of the symptoms, especially when the symptoms go on for a long time or are particularly severe.
  • Dissociative disorder (also called 'conversion disorder' or 'dissociative-conversion disorder') – where it is thought that symptoms that look like they are caused by a disease of the nervous system (e.g. fits, paralysis, loss of memory), but are in fact caused by stress.
  • Health anxiety (sometimes called hypochondriasis) - where someone worries a lot that their symptoms mean they have a serious physical illness, despite reassurance that they are not physically ill.
  • Body dysmorphic disorder –  where someone is overly concerned about an aspect of their appearance, which causes them considerable distress or gets in the way of everyday life.

Other diagnoses can be given for medically unexplained symptoms, but it is common to use a general term to describe the symptoms, such as “medically unexplained symptoms”. 

Another common term is “functional” - the symptoms are due to a problem in the way the body is functioning, even though the structure of the body is normal.

You may wonder if you should have investigations for your symptoms, such as a blood test or a scan. 

Your doctor can discuss with you what investigations you need for the symptoms you have, and when enough tests have been done, to look for anything important.

It is often unhelpful to have investigations that are unlikely to show anything:

  • Tests may be painful and carry a risk of harm.
  • Unnecessary investigations that don’t show anything are often not reassuring. They can make someone worry even more that there is something still to be found and that more tests are needed.

Tackle other stresses

Are there any stressful things going on in your life that might be affecting how you feel? 

Can you talk to someone about these? Can you get any help or advice to manage the situation? By reducing stress you might find that your symptoms feel better too.

Make your life healthier

If you feel generally healthier, you may find that your symptoms bother you less. Try to eat healthily and cut down on smoking and alcohol. Try to get enough sleep and have a regular sleep routine that you stick to.

Take regular exercise

Exercise can help to strengthen muscles and generally make us more fit.  However, don’t overdo it, or this might just make you feel more tired and unwell - build up gradually.

Find time to relax

Relaxation often can help you to manage your symptoms. This might be making time for you to do something that you enjoy or that distracts you from your problems. 

You might also find learning some relaxation techniques helpful. There are many self-help books and websites available.

Stop looking for reassurance and information about your symptoms

If you find that you spend a lot of time worrying about your symptoms, try to remember that repeatedly looking for reassurance or information can be unhelpful. 

Reassurance often doesn’t last long and the worry quickly comes back. 

Similarly, spending too much time looking for information about your symptoms – such as on TV, in books or on the internet – can make you more convinced that there must be a physical illness to account for your symptoms.

When might I need treatment for my symptoms?

If you find that an explanation of the cause of your symptoms and self-help aren’t effective, your doctor might suggest other treatments. 

Your doctor might refer you to a psychiatrist or psychologist who has experience of helping people with medically unexplained symptoms. 

Often they will ask you about your symptoms, as well as your life in general, to help understand how the two can be linked. 

This can also help to decide what treatments might suit you best.

Antidepressant drugs

Antidepressants are used to treat a range of problems, not just depression, and can help treat medically unexplained symptoms in a number of ways.

  • Sometimes, the symptoms are part of anxiety or depression.  In which case, the symptoms will improve if the depression or anxiety is successfully treated with antidepressants.
  • A vicious circle can be set up between symptoms, such as pain and depression. Antidepressants can help break this vicious circle and both the depression and the symptoms can improve.
  • Some antidepressants act as pain-killers and may be prescribed for chronic pain, even when someone is not depressed.
  • Antidepressants can help to treat a range of medically unexplained symptoms, even when someone is not depressed.  We are not sure exactly how they do this, but the evidence shows that they do work.

Before you start an antidepressant, you should discuss the possible side-effects with your doctor. 

People with medically unexplained symptoms may notice more side-effects than others, partly because they may be looking out for bodily symptoms. 

Knowing what to expect can help you to cope with any side-effects. If you do get these, and you can put up with them, they tend to improve after the first couple of weeks.

It is worth trying antidepressant treatment for 2 to 3 months before deciding that it has not worked.

Talking therapies

There are different types of talking therapies that can help. The choice of therapy depends upon the sort of problem and what therapies are available.  These therapies commonly help you to:

  • recognise what seems to make your symptoms worse
  • manage stresses that might contribute to the symptoms
  • develop ways of coping with and living with the symptoms.

Some of the most commonly used talking therapies to treat medically unexplained symptoms are described below.

Cognitive behavioural therapy (CBT)

CBT can help you to identify unhelpful thoughts about yourself and your health, which can make symptoms worse. 

For example, someone may worry that, because people in the family have been ill, they are bound to get ill too. 

Or they may think that they need to have all possible tests done in case something is missed. 

CBT helps people to recognise and tackle these unhelpful thoughts and to develop ways to change the way they think and behave, which can improve their symptoms.

Psychodynamic therapy

This can be particularly helpful when early life experiences affect the way we think, feel and act. 

For example, people who have experienced major difficulties as children seem be more likely to have medically unexplained symptoms as an adult. 

The therapy helps people to understand how and why their symptoms occur, and to develop ways of coping.

Problem-solving therapy and solution-focused therapy

These therapies help you identify and tackle specific problems in your life that seem to be making the symptoms worse.

Most people who see a doctor with bodily symptoms that are not due to physical illness are helped by talking about how their symptoms are caused and what they can do to help themselves.

Some people have symptoms for a long time, especially in the following circumstances:

  • if they are under a lot of long-term stress;
  • if they have had a lot of medical appointments and investigations.  It is not always easy to understand that there may not be a single physical cause for the symptoms if doctors have spent a long time looking for a physical illness.

Even if you have had symptoms for a long time, there is much that can be done to help you live a better life and to avoid unnecessary treatments or investigations.

Functional and dissociative neurological symptoms: a patient’s guide

This website has been compiled by neurologists and gives detailed information about neurological symptoms (such as weakness, numbness or blackouts) which are not due to neurological disease.

Non-epileptic attacks

This website is compiled by health professionals for patients.  It gives information about attacks which look similar to epileptic seizures, but which are not due to the abnormal electrical activity in the brain that causes epilepsy.


  • Assessment and management of medically unexplained symptoms (2008) Hatcher S and Arroll B. British Medical Journal 336: 1124-1128.
  • Efficacy of treatment for somatoform disorders: a review of randomized controlled trials (2007) Kroenke K. Psychosomatic Medicine 69:881-888.
  • Functional somatic syndromes (2007) Page L and Wessely S.  In: Handbook of Liaison Psychiatry, editors: Lloyd GG and Guthrie E.  Cambridge University Press.
  • Medically unexplained symptoms, somatisation and bodily distress.  Developing better clinical services (2011) Editors: Creed F, Henninsen P, Fink P.  Cambridge University Press.
  • * The epidemiology of chronic syndromes that are frequently unexplained: do they have common associated factors? International Journal of Epidemiology, Volume 35, Issue 2, 1 April 2006, Pages 468–476, Aggarwal V R, McBeth J, Zakrzewska JM, Lunt M, Macfarlane G J

About this information

This information was produced by the Royal College of Psychiatrists Public Education Editorial Board and the Faculty of Liaison Psychiatry.

Series Editor: Dr Philip Timms

Authors: Dr Jim Bolton & Dr D Attard

This leaflet reflects the best available evidence available at the time of writing.

Published: Nov 2015

Review due: Nov 2018

© Royal College of Psychiatrists