Skip to main content

Below are some rare and unusual multiple sclerosis symptoms, but they are not the only ones that can occur. If you’re living with MS, or a concerned family member or friend, it is very important to discuss any changes with your healthcare team.

Navigating unusual symptoms will often require communication between multiple doctors, nurses and specialists as other causes are investigated. You may be feeling anxious and uncertain, and it can be challenging to describe the symptoms you’re experiencing but your MS nurse or neurologist can help.

If you’re experiencing any new or worrying symptoms, reach out to your healthcare team or you can make a free appointment with our experienced MS Nurses by calling 1800 042 138.

Uncontrollable or inappropriate crying and laughing: Pseudo bulbar affect (PSA)

Pseudobulbar affect (PSA) is a symptom that is not rare but is uncommon and certainly unusual. Neurologists describe it as pathological crying of laughing. With PSA, a person laughs in outbursts when they don’t think something is funny, or really sob cries when they don’t necessarily feel sad. It occurs when the circuits in the brain between an actual emotion like sadness, and the outward expression of the emotion, like crying, are disconnected. This symptom can be incredibly frustrating and debilitating, leading to social isolation and depression. There are some medications that may help with this symptom.

Loss of humour can also be a rare symptom in MS, it’s not related to pseudobulbar affect, but can occur independently.

Itchiness (or pruritis)

Itch associated with MS should really be called something more than itch, because it can be so debilitating, difficult to treat and dramatically impacts quality of life. MS itch is a sensory disturbance, like the sensory pain, that can be symptom of MS. The medications used are often then the same as those used to treated MS sensory disturbances and pain. In clinical practice, people with MS often needed lifestyle changes to cope with the itch, wearing different types of clothing was a common change people made, sometimes dietary changes also helped. MS itch can occur in unusual places. Some people described to me the sensation feeling like their itch was inside their skull and came on tiny bursts rather than constant, for others it was constant and resulted in substantial skin damage. Itch itself can be caused by many things. It’s important to make sure all other possible causes are ruled out by working with a dermatologist.

Itchiness is one of a group of MS symptoms that are called Paroxysmal symptoms. These are symptoms that occur in by multiple, brief, sudden onset, and typical episodes. They can occur as motor (muscle and movement) symptoms, sensory or pain, visual, or other more usual symptoms.

Intractable hiccups

Intractable hiccups is another paroxysmal symptom of MS. Intractable hiccups are hiccups that don’t go away for weeks to months. Hiccups can also occur unrelated to MS and are more common in another condition more closely related to MS called Neuromyelitis Optica (NMO). Intractable hiccups are extremely uncomfortable, can be painful and may require hospitalisation for treatment.

Intractable vomiting

Can also be a rare paroxysmal symptom of MS that can be associated with hiccups or occur on its own.

Hearing loss

Impaired hearing due to MS happens in less than 6% of people with MS. Deafness, in one or both ears, is even more unusual. That’s why when a lovely 17-year-old girl came to clinic and told me she was deaf in one ear, I was concerned. There were multiple other investigations undertaken to rule out other causes. We also gave IV steroids, as we knew there was a chance this was a relapse, albeit unlikely. A new lesion on MRI confirmed it was an MS relapse and with treatment, the hearing loss resolved. Over my years in MS nursing, I saw only three other people experience MS related hearing loss.

Crocodile tears

The term crocodile tears apparently comes from the ancient belief that crocodiles weep after killing their victims. I’m not so sure about that, but I do recall meeting two people with MS having what is called ‘crocodile tears’ symptom.

Crocodile tears symptom, also known as Bogorad syndrome, is the shedding of tears while eating or drinking in patients recovering from Bell’s Palsy (a facial weakness) which can occur in MS. It is also referred to as gustatory lacrimation. This symptom can resolve over time, physiotherapy can be of benefit and there are various treatments available such as Botox.


Pseudoathetosis is abnormal writhing movements, often of the fingers, that is caused by damage to the pathways of the brain that transmits and processes the information about where your body is in space, called proprioception. Reports of Pseudoathetosis in MS are extremely rare, so I was surprised when a young man in his early twenties came to our clinic with this symptom. His description over the phone of his ‘fingers just randomly moving all over the place’ made not very much sense to me. After excluding other causes, it was clear that his symptom was part of his MS relapse, and once his relapse was treated and a more effective MS treatment started, the symptom fortunately resolved.


Seizures (epileptic seizures) occur in about 2-5% of people with MS. Seizures are the result of abnormal electrical discharges in an injured or scarred area of the brain (usually specific locations) While seizures may occur as part of MS, they may also be the result of an infection, fever, or abrupt cessation of certain medications. It is vitally important to speak to your medical team if you are experiencing symptoms that could be seizures.

Seizure symptoms depend on the type of seizure you're having, but in general, could include:

  • Loss of consciousness or awareness
  • Confusion, behaviour changes
  • Falls with no recalls or warning
  • Strange sensations and emotions
  • Uncontrollable jerking movements of arms and legs
  • Staring
  • Aura

These are not the only rare and unusual MS symptoms. If you are a person living with MS, or a concerned family or friend, it’s very important to discuss any changes, no matter how unusual, with your health team.

It is not uncommon for these symptoms to take longer to investigate as often other causes need to be excluded. They can also be challenging to describe. This can be a very distressing time for people, as uncertainty and anxiety add to what can already be a debilitating symptom.

Navigating unusual symptoms can also often require communication amongst multiple doctors, nurses and specialists, which can be frustrating. MS specialist neurologists and MS nurses who have many years of experience in MS are more likely to have heard these symptoms before and can be a useful resource. If you are concerned, please reach out to our experienced MS Nurses at MS Plus on 1800 042 138

Get news and updates from MS Plus

Sign up