Symptoms
Why symptoms differ
A symptom appears when damage interrupts a pathway that carries a particular signal: from the eye to the brain, from the brain to the leg muscles, from the bladder to the spinal cord. Which symptoms a person has depends on where their lesions are, not on how many there are. One small lesion in the spinal cord can cause more difficulty than many lesions in parts of the brain that the brain can work around (lesson 6.2). This is why two people with similar scans can have very different experiences of MS.
The first symptoms
- Eyes
Optic neuritis causes blurred or dim vision in one eye, washed-out colours and pain on moving the eye. Brainstem lesions can cause double vision.
- Face
Numbness of the face, and trigeminal neuralgia, a brief severe stabbing pain, in about 4 per cent.
- Arms and hands
Numbness, tingling, clumsiness and weakness. Arm and hand function is measured in trials with the nine-hole peg test.
- Legs and walking
Weakness, stiffness, poor balance and fatigue together cause most walking difficulty.
- Bladder and bowel
Urgency, frequency and waking at night to pass urine, difficulty emptying the bladder, and constipation.
- Brain
Fatigue, slower thinking, difficulty with attention and memory, and low mood or anxiety.
- Skin
Numbness, tingling, burning pain and a band-like tightness around the trunk or limbs.
The first symptoms often come as an attack that develops over days. Common first attacks are:
- Optic neuritis: blurred or dim vision in one eye, colours looking washed out, and pain when moving the eye.
- Sensory symptoms: numbness, tingling or a tight band-like feeling, often spreading over days.
- Brainstem symptoms: double vision, dizziness or unsteadiness, or numbness of the face.
- Spinal cord symptoms: weakness or numbness in the legs, bladder urgency, or a brief electric sensation down the spine when bending the neck, called Lhermitte's sign.
In progressive MS from onset, the first symptom is more often a slowly increasing difficulty with walking.
Fatigue
Fatigue is one of the most common symptoms and often one of the most limiting. It is an overwhelming tiredness that is out of proportion to effort and not fully relieved by rest. A meta-analysis of studies worldwide estimated that 59 per cent of people with MS have it, with estimates varying mainly with the questionnaire used. Poor sleep, low mood, pain, infections and some medicines can add to it, so these are checked when fatigue worsens.
Walking, balance and stiffness
Weakness, poor balance and spasticity, a stiffness of the muscles with spasms or cramps, together cause most walking difficulty. Walking is measured closely in trials because it drives the EDSS from 4 upwards (lesson 7.1). Fampridine, physiotherapy and exercise can help some people walk further or more safely (lesson "Treating relapses and symptoms" in Module 11).
Bladder, bowel and sexual function
Damage to the spinal cord pathways that control the bladder causes urgency, frequency, waking at night to pass urine, and sometimes difficulty emptying the bladder. Constipation is common, and sexual function can be affected in both men and women. People often do not raise these symptoms themselves, so UK guidance recommends that regular reviews ask about them directly.
Pain
Pain is more common than many people expect. A meta-analysis of 17 studies with 5,319 people found pain in 63 per cent. Headache was reported by 43 per cent, burning or shooting pain in the limbs by 26 per cent, back pain by 20 per cent, Lhermitte's sign by 16 per cent, painful spasms by 15 per cent and trigeminal neuralgia, a severe stabbing pain in the face, by about 4 per cent.
Thinking and mood
Changes in thinking are common and can begin early, even without much physical disability. The most typical are slower processing of information, and difficulty with attention, planning and remembering new information. They can affect work and daily life more than physical symptoms, and they are measured in trials with tests such as the Symbol Digit Modalities Test.
Depression and anxiety are more common in MS than in the general population. A systematic review of population-based studies found depression in about 24 per cent and anxiety in about 22 per cent of people with MS. Both are treatable, and both can worsen fatigue and thinking.
Symptoms that come and go
Many symptoms change from day to day without any change in the disease. Heat, from a hot bath, exercise or fever, slows conduction in nerve fibres that have lost myelin, so old symptoms can return for a while. This is Uhthoff's phenomenon, and it settles as the body cools (lesson 1.2). Some symptoms come in brief repeated episodes lasting seconds, such as spasms or trigeminal neuralgia. A new symptom, or a clear worsening, that lasts more than 24 hours without fever may be a relapse and is worth discussing with the MS team (lesson 4.2).
Common questions
Does a symptom getting worse in the heat mean a relapse?
Usually not. Heat can bring back old symptoms for hours, and they settle as the body cools. New symptoms lasting more than a day are different.
Do more symptoms mean the disease is getting worse?
Not necessarily. Symptoms fluctuate with heat, infection, sleep and stress. Worsening that persists over months is what doctors look for when they assess progression.
What we know
- Symptoms depend on where lesions are, which is why they vary so much between people.
- Fatigue, pain, bladder problems, changes in thinking and low mood are common and often under-reported.
- Heat and infection can bring back old symptoms temporarily without new disease activity.
What we don't know
- Why fatigue is so common and what causes it at the level of brain cells.
- How to predict which symptoms a person will develop.
- Which treatments work best for fatigue and changes in thinking. The trials are mostly small.
In the research now
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Key terms
- Lhermitte's sign
- A brief electric sensation down the spine or limbs when bending the neck, from a lesion in the neck part of the spinal cord.
- Optic neuritis
- Inflammation of the optic nerve, causing blurred vision and pain on moving the eye. Often the first symptom of MS.
- Uhthoff's phenomenon
- A temporary return or worsening of symptoms with heat or exercise, caused by slower conduction in demyelinated fibres. It is not a relapse.
- Myelin
- The fatty sheath wrapped around many nerve fibres in the brain and spinal cord. It lets signals jump quickly along the fibre. MS damages it.
- Axon (nerve fibre)
- The long extension of a nerve cell that carries its signal. Losing axons, rather than myelin alone, is thought to cause most lasting disability.
- Lesion (plaque)
- An area of damage where myelin has been lost and the tissue scarred.
- Relapse (attack)
- New or worsening symptoms lasting at least 24 hours, without fever or infection to explain them.
- EDSS
- Expanded Disability Status Scale, from 0 (normal examination) to 10, the main disability measure in trials. Its middle range depends heavily on walking.
References
- Yi X, et al. Global prevalence of fatigue in patients with multiple sclerosis: a systematic review and meta-analysis. Front Neurol 2024. doi:10.3389/fneur.2024.1457788https://doi.org/10.3389/fneur.2024.1457788
- National Institute for Health and Care Excellence. Multiple sclerosis in adults: management (NG220). 2022. https://www.nice.org.uk/guidance/ng220https://www.nice.org.uk/guidance/ng220
- Foley PL, et al. Prevalence and natural history of pain in adults with multiple sclerosis: systematic review and meta-analysis. Pain 2013. doi:10.1016/j.pain.2012.12.002https://doi.org/10.1016/j.pain.2012.12.002
- Chiaravalloti ND, DeLuca J. Cognitive impairment in multiple sclerosis. Lancet Neurol 2008. doi:10.1016/S1474-4422(08)70259-Xhttps://doi.org/10.1016/S1474-4422(08)70259-X
- Marrie RA, et al. The incidence and prevalence of psychiatric disorders in multiple sclerosis: a systematic review. Mult Scler 2015. doi:10.1177/1352458514564487https://doi.org/10.1177/1352458514564487
- Waxman SG. Axonal conduction and injury in multiple sclerosis: the role of sodium channels. Nat Rev Neurosci 2006. doi:10.1038/nrn2023https://doi.org/10.1038/nrn2023
Next · Lesson 2 of 3
How MS is diagnosed
There is no single test for MS. A neurologist combines the story of the symptoms, an examination, MRI and sometimes spinal fluid, and confirms MS only when no other disease explains the findings better. This lesson explains how the 2024 diagnostic criteria do that.
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