Doctors often face a dilemma. Is an illness physical or psychological? Isn’t not always clearcut. Getting it right can make a big difference to the patient and equally, getting it wrong can lead to a lot of frustration.

Diagnosis is tricky and to complicate matters further there’s no physical illness that doesn’t affect the mind in some way, ranging all the way from mild annoyance to a complete change of personality.

        Take this story I heard of a middle-aged immigrant from Bangladesh. She goes to see her GP and says she is in pain. She melodramatically explains that she has pain here, there and everywhere, pointing to her arms, her chest, her legs and all parts of her body. Her initial tests are normal and her doctor, not unreasonably, puts it all down to depression or to her difficult living conditions.

But the doctor was wrong. Eventually someone does a vitamin D level and the true cause reveals itself. Her blood levels are found to be down in her boots. Many immigrants are at high risk of severe vitamin D deficiency due to their darker skins, unsuited to cloudy British skies, and with spending too much time indoors. Treatment soon starts to make a difference.

In ecological medicine we see many patients who’ve been told it’s all in their mind. Classic situations are chronic fatigue syndrome, food intolerances, multiple chemical sensitivity and electromagnetic hypersensitivity (EHS). These patents express immense frustration at being told it’s all in their head. And they know it’s not true.

Even in conventional medicine diseases such as an overactive thyroid can present with largely psychological symptoms and fool the doctor if the appropriate tests are not done.

And the reverse can happen. Psychological illnesses can be wrongly diagnosed as physical ones.

  Are doctors too quick to think it’s all in the mind? I believe yes. And there’s one situation where this happens time and time again.  That’s in those illnesses where tests come back normal. Sometimes the patient is told bluntly: we can’t find anything wrong with you, so it must be all in your mind. This is unhelpful, to say the least.

But there’s a basic error in thinking here. Having normal tests doesn’t indicate a mental problem. Far from it. What it does indicate is that certain conditions have been excluded but only those conditions that produce an abnormal test. Many illnesses don’t (like chronic fatigue syndrome and food intolerance, for example).

There has to be a better way. How can we avoid these frustrating errors of diagnosis?

Listening carefully to the patient’s story can prevent all sorts of diagnostic mistakes. If a patient says they only have symptoms when they are exposed to a certain food, chemicals or even electromagnetic radiation, they are usually right, no matter how the tests come back, and they are, in fact, telling the doctor the diagnosis, even if the doctor is unfamiliar with it.

I don’t pretend it’s always easy. Many years ago, I read a brilliant paper by Canadian psychiatrist Dr Ralph Shulman (Lancet, 1977, 524-6). Under the heading “guide to the perplexed” he made ten suggestions coupled with some fascinating case histories to illustrate about how to avoid these errors.

In particular he suggests it is best to admit to uncertainty in diagnosis before jumping to the conclusions. Saying you don’t know is more honest than saying it’s all in the mind.

He suggests before making a judgement that it’s a mental issue, the doctor needs to make a direct enquiry into symptoms of depression and similar symptoms. In other words, he needs to make a positive diagnosis of a mental health problem (rather relying on negative tests).

New symptoms in a chronic condition should be regarded with suspicion.  He feels that patients with a history of psychological problems like depression can get a raw deal. They are particularly at risk of being given a psychiatric label whatever they present with. A change in the pattern of symptoms may be a clue to a different and perhaps more serious, illness.

He gives an example of a doctor with a history of anxiety neurosis who was unable to attend autopsies because of persistent nausea and vomiting. A neurologist and gastro-enterologist found no physical disease. A psychiatric diagnosis was made. But it turned out that he had a brain tumour. The clue was that his anxiety had never interfered with his work as a physician before. There are always pointers, even if subtle.

He also suggests asking the patient why they have come now, when were they last their normal self, how does it affect their life, was there any change in circumstances when the illness started, have they had a similar pattern of illness before (anxiety and depression usually follow the same pattern in a particular person over time).

Of course, sometimes patients present with a physical problem which does have a psychological origin. Oddly enough, asking the patient what they think is wrong with them is a good starting point. If a patient has convinced themselves they have cancer or heart disease, as often happens, telling them that their tests are normal won’t help one jot. But understanding their concerns and explaining why they haven’t got that particular illness can lead to immense relief.

There is not always time to ask all these questions in a busy surgery but my hope is more doctors will think twice before judging that it’s all in the mind, unless there is good evidence of this.