by Dr Steve McCabe

Before I went to medical school the word functional meant to me something that was reliable, practical and useful but also rather dull and mundane. But I soon learned that 1980s medical education had a whole different definition for functional.

In that world it was used as a term to describe symptoms for which a medical diagnosis could not be found.

It was also used, in a pejorative way, to label people with such symptoms, implying that, at best, they were making things up or, at worst, that they were mentally ill.

Fast forward twenty years and the term ‘functional’ had been replaced by the phrase ‘medically unexplained symptoms’. But for many doctors the underlying implications remained.

And now things have turned full cycle and ‘functional’ is once again an accepted medical term except this time the stigma has been much reduced (though, sadly, not altogether eliminated).

Diseases for which we have reliable, observable and measurable tests or investigations are referred to as ‘organic disease’. ‘Functional’ (or nonorganic disease) refers to symptoms in the absence of known and measurable processes.

They were previously regarded as a psychological issue and often referred to as psycho-somatic symptoms. But that is no longer the case.

It’s true to say that mental health problems such as depression, chronic anxiety, psychosis, attention deficit disorder or post-traumatic stress are functional conditions. But they are only part of the picture.