Functional Neurological Disorder – Pushing the boundaries of medical credibility?

31st May 2022

Whilst doing my ward round I came across a patient who was being attended to by one of the junior doctors, a 12 year old boy who had been admitted with “seizures”, a relatively common condition which most paediatric trainees should feel comfortable in managing. The patient, let’s call him Peter (not his name), had a previous diagnosis of “functional neurological disorder” (FND for short) and my junior was about to discharge this patient home despite the fact that the parents had brought their child to hospital because of the severity of his symptoms, because they were desperate and had been desperate for the past three years with a child who was house bound, unable to function on a day to day basis, unable to attend school and unable to experience a normal childhood. The patient raised my curiosity but before I discuss the management let’s take a look at FND, what it is and how the term came into being.

To fully understand FND we need to go back to Hippocrates who in 400 BC coined the term “hysteria” to describe unusual symptoms in patients which he felt were due to the uterus wondering around the body (hysteria is Greek for womb). This term was used to describe patients with unusual neurological or psychiatric symptoms that could not be explained by conventional medicine. Fast forward to the 19th century and we meet Jean-Martin Charcot, often described as the father of neurology who worked  at the Salpetriere hospital in Paris. Charcot performed autopsies on the brains of patients who had been diagnosed with hysteria and who had subsequently died, despite his efforts he did not find any anatomical abnormalities that could explain the symptoms that these patients had experienced. This was at a time when the battle between those who believed in the disorders of the mind versus those who believed in a physical or organic explanation of patients symptoms were particularly fervent. put in modern terms this was the battle between the molecule and the mind. One of Charcot’s pupils was Gilles de la Tourette who went on to describe Tourette’s syndrome following encouragement from Charcot.

In the twentieth century the baton was picked up by Joseph Babinski, Pierre Janet and Sigmund Freud. Freud championed the idea that hysterical symptoms (ie those symptoms that could not be explained by conventional medicine) were likely to be due to repressed trauma, abuse or other disturbing events and hence the term “conversion disorder” was coined. This led to a movement of patients with “hysteria” away from neurology to psychiatry. Over the next few decades Freud’s influence diminished and so did the number of cases of conversion disorder. Conversion disorder was seen as a disease of the Victorian era.

Conversion disorder fell out of favour until 2013 when a group of physicians were concerned that the concept of conversion disorder would not be accepted in modern society. They therefore lobbied for a new term “functional neurological disorder” to be included in the DSM-5 catalogue (this is an indexing system that ascribes a code to a medical condition allowing it to be monitored but also giving it credibility).

So we now have functional neurological disorder (FND) to help assign a label to complex symptoms in patients who do not fit conventional medical explanations but just how useful is it? Some of my juniors joke that FND=finding no diagnosis. It would be funny if it wasn’t for the tragedy associated with this condition. Protagonists of FND recommend a “bio-psychosocial” approach to manage these patients with input from CAMHS and the use of CBT etc etc. This unfortunately is not the real world where patients are often waiting months or years for a CAMHS review and even if they are reviewed they are often directed to self-help websites on parenting skills. As one of my colleagues put it: “I have yet to meet a patient who has benefitted from receiving a diagnosis of FND”. My concern is that once a child receives a diagnosis of FND, the diagnostic process stops and people stop being inquisitive.

So let’s go back to Peter, a 12 year old boy with tics, obsessive compulsive behaviours and a strange seizure like phenomenon that occurs 200 times a day. The seizures are unusual in that he cannot respond during an attack, his limbs go into a foetal position with rhythmical beating and his eyes deviate to one side. Occasionally he can hear what is going around him but cannot respond. The build up to a seizure is cumulative with a sudden drop, something I have termed a “capacitance effect” because it is like a capacitor discharging its charge. He had been investigated with an EEG and MRI but both returned normal and he was subsequently given a diagnosis of FND. I had seen this before so I asked my junior to run some tests and then started some treatment. Peter’s symptoms improved by 80% within two weeks, he was able to function normally and started to attend school.

This was not a case of functional neurological disorder, conversion syndrome, non-organic disease or hysteria but rather an immune mediated behavioural change that could have been detected if the right tests had been requested and the right treatment started, I would estimate that there are at least another 20 cases around the UK right now which are like Peter and most of whom have previously been given a diagnosis of FND. As one of my juniors put it, “you only know what you know”. The battle between those that subscribe to the molecule versus those that subscribe to the mind will continue for now, our job as doctors is to try our very best to ensure that the patients we encounter are met not only by doctors with experience but also by doctors who have the humility to consider diagnoses beyond their own specialisations only then can we effectively treat those patients who sit on the boundaries of conventional medicine.

Dr Tim Ubhi


Posted in: Children's Health Topics, Health Politics, PANDAS by Dr Tim Ubhi


John W

2024-06-06 10:38:47

Some one commented on here saying these 3 words FND can basically finish you, How correct are they I went in hospital with stroke like symptoms after 3 days a neurologist come up to me and said you have FND within 30 seconds, ever since then every consultant I have seen just send me home my condition is getting worse I am falling my walking is really bad they said you are 59 what do you expect Doctors just say you are a loony and don’t listen to you I am getting worse 3 years on and no one is interested people see with there own eyes but they just say FND nothing we can do, My left side I can hardly use my hands I have trouble getting them to work properly Are more people getting a FND diagnosis because it is easy for them but for the patients you are left to get on with it no help no support nothing


2024-03-25 15:30:05

Your anonymous patient is so wife who had scoliosis correction surgery at age 42 with Harington Rods inserted, removed after 3 years as problems with the metal being accepted by the body. At 46 my wife had a serious hestorectimy operation which we think caused the developement of scar tissue and resulted in a complete bowel obstruction and emergency surgery at 59 years no sign ever having showed up in scans! At 63 my wife suddenly had a complete change in her ability to walk and has pain and pins and needles in both legs. She can still walk but quickley reaches exhaustion point when out. She is 5 ft 6 inch, weighs 8.5 stone and fairyly constatnt. An FND diognosis at a major London Teaching Hospital Neurology department has caused a complete lack of respect from Orthodedic depatment although my wife believes that the problem lies with her back, the original scoliosis, and possibly spinal stenosis. They have virtually obstructed all attempts at getting a second opinion


2023-12-28 16:40:10

My daughter is autistic, aged 17, and attending 6th form, currently having approx 3 seizures a week. She had to leave her previous school in Feb as she was suffering up to 9 seizures in a morning. She was diagnosed with severe social anxiety and FND after tests ruled out epilepsy. Is there anything else we can try?


2023-08-22 22:51:07

Thank you Dr Ubhi for talking about this. You and some of your readers might be interested in a forum called Science for ME ( which has resources on the problem of FND. The so-called science of FND is critically examined, the people and politics of it are discussed and international advocacy is supported. There are weekly summaries of relevant news. The forum is primarily concerned with ME/CFS, sometimes known as chronic fatigue syndrome, and similar post-infection diseases including Long Covid. These illnesses are often included in the bucket of poorly understood conditions labelled with FND.

Mandy Gray

2023-06-16 13:48:01

I am desperately looking for a doctor who will give IVIG to my adult son who is living in London. He was diagnosed with PANDAS in Australia and received IVIG monthly for 8 years under Dr Russell Dale initially. He was exactly like you describe Peter but within 5 months of IVIG his severe symptoms diminished incredibly. In the last couple of months his tics and OCD have sky-rocketed. He has now been without IVIG for a year and we just need the contact name of a doctor who might be willing to give IVIG - even enough to get him through the next couple of months when he can maybe come home


2022-07-30 20:07:22

Thank you so much for writing this - and Peter was lucky to be found by a doctor like you - your junior doctors are also lucky to have you. My daughter was diagnosed as having FND by a neurologist prior to them even meeting my daughter. Let alone carrying out any tests on her. I had to fight the neurologist to get them to do an MRI - turns out she has Chiari malformation and Syringomyelia.

Jaye Wood

2022-07-16 17:36:49

I've lost just over 4 years to these three letters which were given very quickly along with an instant discharge from neurology and a website scribbled on a piece of paper, largely, I suspect due to a history of anxiety and depression since adolescence. There has been *no treatment* as if these three letters magically make it disappear. I am fortunate to have a listening and determined GP who is investigating other endocrine, rheumatic and neuromuscular possibilities, most recently seeing a big improvement with pyridostigmine bromide, so its looking increasingly like myasthenia gravis, which was dismissed on a single negative blood test, negative in up to 50% of cases of ocular myasthenia. I cannot tell you how damaging those three letters are, both psychologically and physically. It is a hugely worrying trend and this "rule in" tendency is easily exploited. Thank you so much for looking beyond those three letters and championing the cause of those too easily labelled with this "Emperor's New Clothes" diagnosis.


2022-06-06 14:35:39

Do you know of any adult doctors (preferably neurologists) in the UK willing to look past an FND diagnosis to do further tests? I’ve studied a lot on FND and it’s academic literature and it doesn’t fit. I don’t even meet the “rule in” criteria for it, but I can’t find anyone willing to look past my FND diagnosis and try to find an actual explanation for what’s going on. Your article gave me hope, but I still don’t know who to go to. I’m willing to pay for a private consultation if needed.

Catherine Carlson

2022-06-01 16:05:57 I wrote another two other articles that debunk FND and PNES diagnoses but the journal has disappeared (Journal of Neurology and Psychiatric Disorders). This is the correct name of the journal for references 61 and 62 in above-cited link.


2022-06-01 16:05:00

My child was taken by child ‘protection’ because of this presentation and I am urgently trying to get them home and safe. Are there specific tests or advice you could give to pass to my lawyer at all? They accused me of FII even though psychiatrist denied it and they are ignoring all her symptoms and says she makes it up. It is torture and the damage is so great.

Philippa Haydon

2022-06-01 11:57:08

My son presented exactly as the patient you described. He was 11, sudden onset vocal and motor tics, (well over 200 per day and complex), then jerking seizure like movements of arm and leg on one side. Next came collapsing and what looked like loosing consciousness, (eyes were closed) but would come to and could describe what we had been saying to him. He was given a conversion disorder diagnosis despite no trauma. He then developed paranoia and attachment issues, followed by amnesia that looked like delirium plus poor cognition. The last stage was debilitating fatigue, POTS (resting >90 bpm, standing >180bpm), profuse sweating and inability to regulate temperature, joint pain, constant severe headache (described as brain to big for skull), light sensitivity due to dilated pupils, chronic digestive issues and skin sensitivities. He now receives IVIg under Prof Russell Dale as is regaining his life.


2022-06-01 08:33:34

Love how you said an immune mediated behaviour change. There is so much more going on in the body to consider for each symptom.

Dr Tim Ubhi

2022-05-31 22:26:21

Please look at the GP section on the PANDAS page at the Children’s e-hospital


2022-05-31 22:22:32

What are the tests and treatment you refer to in the " right tests had been requested and the right treatment started" . My daughter has been diagnosed with FND and I would love to know so she can get help.


2022-05-31 22:14:16

Thank you for writing about this. We had a very similar experience indeed with seizures and mention of an FND diagnosis. Luckily we found an infectious cause, treating that and the inflammation led to huge improvement. FND diagnosis would have got us nowhere and no help. It's a meaningless diagnosis too easily given out when an anwser can't easily be found. This definitely needs calling out so thank you.

Sarah hughes

2022-05-31 21:59:39

Please can you write this patient up as a case study and publish it in a peer reviewed publication? Just the patient case study, no doubt the wider debate about FND would lead to it being rejected.

Nicola L

2022-05-31 21:09:40

My daughter has exactly these issues, sudden onset tics and FND diagnosis. Currently in a psych unit last 2 years and little to no progress. Am struggling to get her professionals to listen to the possibility of immune mediated disease causing her problems and act accordingly. The system needs to change. When information is staring them in the face they still dismiss it.


2022-05-31 21:06:20

So how do we educate medical professionals on how to look further because they seems to be the main problem .They are either too quick to judge, have no experience or can make assumptions without doing further tests to rule anything out.i appreciate services are stretched but I always thought we should trust the Drs till my daughter became I'll. It took a neurologist literally 2min to day my child had this without speaking to us based on history.


2022-05-31 21:04:41

So how do we educate medical professionals on how to look further because they seems to be the main problem .They are either too quick to judge, have no experience or can make assumptions without doing further tests to rule anything out.i appreciate services are stretched but I always thought we should trust the Drs till my daughter became I'll.

Leave a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.