While most people associate multiple sclerosis (MS) with muscle weakness, numbness, and pain, fatigue is actually the most common symptom of the condition.

Nearly 80 percent of people diagnosed with MS experience fatigue at some point, according to the Multiple Sclerosis Association of America.

Fatigue is defined as extreme tiredness or unrelenting exhaustion. The fatigue associated with MS can be difficult to cope with, and is also difficult to explain to other people. Although it’s an invisible symptom, fatigue is very real for those living with the condition.

The first step to treating fatigue is to find out what’s causing it. Fatigue may be a result of nerve damage caused by MS. Sleep problems, depression, and medication side effects could also be part of the problem.

The good news is that it’s possible to manage fatigue with the right combination of medications, lifestyle changes, and energy-saving tips.

Scientists currently don’t fully understand the exact cause of MS-related fatigue. Some think that fatigue may be related to the constant activation of the immune system, sort of like having the flu virus at all times.

Others theorize that fatigue is related to the need for the brain to work harder in people with MS.

MRI scans have shown that people with MS fatigue use a larger area of the brain to perform tasks than people without fatigue. In response to nerve damage, the brain of a person with MS may be finding new routes for sending messages. This is thought to take more energy.

The feeling of fatigue may also be a result of the muscle weakness associated with MS.

Certain complications of MS can also induce fatigue. This may be referred to as a secondary cause. Complications of MS that may also cause fatigue symptoms include:

Fatigue can also be a side effect of certain medications, such as those used to treat spasticity, pain, and bladder dysfunction.

Not everyone experiences fatigue the same way, and the feeling can be difficult to explain to others. In general, there are two types of MS fatigue: a general feeling of extreme tiredness and muscular fatigue.

MS fatigue is different from regular tiredness. Some people with MS describe the fatigue as feeling like you’re weighed down and like every movement is difficult or clumsy. Others may describe it as an extreme jet lag or a hangover that won’t go away.

For others, fatigue is more mental. The brain goes fuzzy, and it becomes difficult to think clearly. Fatigue may affect the eyesight, as well as your ability to speak without slurring your words.

MS fatigue is also distinguished by the following characteristics:

  • occurs on a daily basis
  • often occurs in the morning even after a good night of sleep
  • tends to worsen as the day progresses
  • is aggravated by heat and humidity
  • may come on suddenly
  • interferes with daily tasks, such as work

Fatigue is difficult to explain or quantify. This is why doctors have developed the Modified Fatigue Impact Scale (MFIS). It’s used to evaluate how fatigue affects someone’s life.

The MFIS takes only 5 or 10 minutes to fill out at a doctor’s office. It includes a series of questions or statements about your physical, cognitive, and emotional health.

You’ll be asked to rate how strongly each statement reflects your experiences over the last month on a scale of 0 to 4, with 0 being “never” and 4 being “almost always.”

Examples of statements you’ll be asked to rate include:

  • My muscles feel weak.
  • I have to pace myself in my physical activities.
  • I have trouble concentrating.
  • I have been less motivated to participate in social activities.

You can find all of the questions and statements on the MFIS here.

The sum of all your ratings is your MFIS score. A higher score means fatigue is significantly impacting your day-to-day life. The score can help you and your doctor come up with a management plan that addresses your particular fatigue symptoms.

If you’re experiencing fatigue, make an appointment with your doctor to discuss possible treatment options. A doctor will likely want to run some tests to find out more about what may be causing your fatigue.

Based on the results of these tests, your doctor may prescribe medications or recommend counseling, physical therapy, and occupational therapy.

Medications

Depending on what’s causing your MS fatigue, a doctor may prescribe:

  • anti-inflammatory pain medications, like aspirin. A 2012 study found that taking 100 milligrams of aspirin twice per day significantly reduced MS-related fatigue.
  • amantadine (Gocovri), an antiviral drug that may help with MS fatigue. Its mechanism for treating fatigue, however, is unknown.
  • armodafinil (Nuvigil) or modafinil (Provigil), which are medications typically used to treat narcolepsy. They’ve shown some evidence of promoting wakefulness in people with MS fatigue, and may also help with sleep issues.
  • iron supplements to treat anemia
  • sleeping pills to treat insomnia, such as zolpidem (Ambien, Intermezzo)
  • multivitamins to treat nutritional deficiencies caused by poor diet
  • antidepressants like fluoxetine (Prozac) or bupropion (Wellbutrin)
  • medications to help with leg spasticity
  • medications for urinary dysfunction, if the need to use the bathroom is keeping you up at night
  • methylphenidate (Ritalin) or dextroamphetamine (Dexedrine), which are normally used to treat attention deficit hyperactivity disorder and narcolepsy. These medications may be used to improve wakefulness and increase energy.

If you think one of your current medications may be causing your fatigue, ask your doctor about the possibility of changing your medication or adjusting the dosage. Don’t stop taking your medication without consulting your doctor first.

People with MS fatigue may need to recharge their batteries with frequent rest and a short daily nap, but it’s also possible to plan and schedule your daily activities to help conserve energy.

To conserve energy, try these tips:

  • Divide large projects into smaller parts.
  • Gather supplies in advance of an activity, like cooking or cleaning, so you won’t have to run around to find supplies while you complete the task.
  • Plan your shopping list in advance.
  • Have your groceries delivered.
  • Cook all your meals for the week at once, if possible.
  • Organize your house so frequently used items are stored in easy-to-reach places.
  • Use wheeled carts to transport heavier items around the house.
  • Make sure you have good lighting in your home so you’re not straining to see things clearly.
  • Consider using adaptive devices for dressing, bathing, and household chores.
  • Keep your house cool if your fatigue tends to get worse when it’s warm.
  • Run a dehumidifier if your fatigue tends to flare up in humid weather.
  • Use a handicap permit and park close to the building.

While conserving energy is important, too much rest can be counterproductive. Exercising daily is essential for maintaining muscle strength and building endurance. Try these exercises and activities for MS.

There are several other lifestyle changes and remedies that can help you battle fatigue. These include:

  • going to physical therapy to learn about ways to conserve your energy and to establish an exercise routine
  • meeting with an occupational therapist to simplify tasks at work or at home
  • practicing good sleep hygiene
  • seeking psychological counseling if you’re depressed or anxious
  • reducing alcohol consumption
  • eating a healthy diet high in fruits, vegetables, whole grains, healthy fats, and lean protein
  • eating a vegan or plant-based diet. A 2016 study found that people with MS who followed a very-low fat, plant-based diet had a significant improvement in fatigue after 12 months.
  • reducing stress. Yoga, meditation, and tai chi are excellent ways to reduce stress and engage in physical activity.

Fatigue is a very common symptom of MS and may be one of the most troublesome. If fatigue is affecting your work or daily life, talk with your doctor to find out if there are any medications you need to be taking or if your current medications need to be adjusted.

You can overcome fatigue with the right combination of medications and lifestyle changes.