Fatigue – extreme tiredness – is one of the most common symptoms of multiple sclerosis (MS), occurring at some point in about 80% of people with the condition. In many people, it’s their most obvious symptom.
The nature of the fatigue differs from person to person. For some people, it’s overwhelming – much worse than ordinary tiredness – and significantly interferes with their ability to function, even confining them to bed for periods. Fatigue may appear and disappear without warning, or it may be a constant mild symptom that makes everything a little tiring.
Fatigue may worsen existing symptoms or trigger new ones. The ability to carry out physical and cognitive tasks can be impaired. You may feel weak and your limbs “heavy”. Concentration, vision and speech can temporarily be affected.
While the cause of MS fatigue isn’t well understood, primary fatigue is thought to be due to the MS itself: the slowing of the nerve impulses and resulting muscle weakness. This kind of fatigue or lassitude, which is unique to MS:
• Is severe.
• Usually occurs daily.
• Appears suddenly, sometimes in the morning.
• Tends to get worse as the day wears on.
• Gets worse with heat and humidity.
Secondary fatigue isn’t directly caused by MS itself, but results from other MS symptoms:
• People with bladder dysfunction, pain or nocturnal muscle spasms may be sleep-deprived.
• People who are stressed or depressed may also suffer fatigue.
• It may be tiring for someone with MS to perform simple daily tasks.
• Tiredness can also result from inactivity.
• Fatigue may occur as a side effect of various medications.
Options for dealing with fatigue include:
• Make use of occupational therapy to simplify daily tasks, and physical therapy to learn new ways of performing them.
• Learn how to conserve energy for the times you need it, and prioritise activities. Rest when you need it. Pace yourself.
• Regulate your sleep, which might involve sleep medications.
• Manage your stress with relaxation training, a support group or psychotherapy.
• Find out what triggers your fatigue – e.g. heat, over-exertion, over-tiredness, heavy meals, smoking or stress – and manage it.
• Keep a diary of daily activities, fatigue and possible fatigue triggers.
• Exercise regularly and stay fit – but not to the point of exhaustion or overheating.
• There are several drugs that may help with fatigue. The antiviral amantadine may improve muscle control and reduce muscle stiffness (although there may be side effects). There are also prescription drugs for sleep disorders that can help – ask your doctor.
• The amino acid L-carnitine is involved in the production of energy in the body. Some research has shown less fatigue in MS sufferers taking supplements containing a form of L-carnitine, although further study is needed.
• If you find it tiring to perform daily tasks, there is assistive equipment available to aid you. It might be possible to employ someone to do some of your housework.
Because fatigue can also be caused by various other medical conditions such as depression or food allergies, always consult your doctor if fatigue is causing you concern.
‘How to Choose the Mobility Device that is Right for You: A guide for people with ms’, National MS Society, 2013; National Multiple Sclerosis Society, www.nationalmssociety.org; Multiple Sclerosis Trust, www.mstrust.org.uk; MUSC Health (Medical University of South Carolina) Multiple Sclerosis Clinic, www.muschealth.com; Life and MS.com – all about Multiple Sclerosis Symptoms, www.lifeandms.com; MS-UK, Choices leaflets, www.ms-uk.org