Are Muscle Twitches a Symptom of MS or ALS? (2024)

Some people experience muscle twitching all over the body everyday. Muscle twitching is more common than you may think and it's usually not serious. Common causes range from too much caffeine and too much stress to strenuous exercise and a lack of sleep. Managing stress and limiting caffeine, for example, may be enough to stop the twitching.

Muscle twitching alone does not necessarily indicate a disease. Other symptoms that something more serious may be going on include muscle weakness or wasting and fatigue. Causes can include multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), thyroid disease, and more.

This article provides an overview of muscle twitching and its common causes, as well as symptoms of other, potentially more serious conditions and advice on when to seek medical care.

What Causes Muscle Twitching?

Muscle twitching occurs when nerves misfire, causing groups of muscle fibers to contract uncontrollably. Muscle twitches are small movements and may go unnoticed.

Fasciculations, or muscle twitches, happen where the tips of the nerves, called axons, meet your muscles. A nerve fires an electrical impulse and triggers the release of a chemical between the axon and muscle, causing the muscle to contract. Involuntary (uncontrollable) twitches have a number of common causes as well as a few rare ones including ALS.

Common Causes

It's important to understand that a run-of-mill muscle twitch here and there is likely nothing to worry about. Twitching can occur in healthy people and rarely signals the presence of an underlying disease, especially if it occurs without other symptoms.

Benign twitches are not caused by a disease or disorder. They'll often affect the eyelids, calf, or thumb and usually won't last more than a few days. Benign twitches can be triggered by a number of things, including:

• Certain medications, such as water pills or steroid medicines
• Exposure to extreme cold
• Hyperventilation
• Strenuous exercise
• Stress or anxiety
• Tiredness or lack of sleep
• Too much caffeine or alcohol

In these instances, muscle twitches are benign and short-lived, meaning they are not a serious health concern, and come and go quickly.

Benign Fasciculation Syndrome

In benign fasciculation syndrome, muscle fibers contract spontaneously and continue to do so. This syndrome is not caused by an underlying disease. People with this syndrome can find it very distressing. However, their symptoms are not caused by a motor neuron disease.

Cramp-Fasciculation Syndrome

Cramp-fasciculation syndrome (CFS) is a rare condition, which causes frequent muscle twitches and muscle cramps. Symptoms often show up in the legs, can affect other parts of the body as well. People with CFS may experience muscle discomfort, pain, and tiredness.

Over-activation of the nerves associated with the twitching muscles is likely what drives symptoms. Symptoms tend to show up in adults. CFS can show up sporadically in people who don't have relatives with this condition.

More Serious Conditions

Lower motor neurons transmit nerve signals from your spinal cord to your muscles. When these nerve signals are disrupted, muscle weakening and wasting will eventually occur, along with uncontrollable muscle twitching called fasciculations.

Fasciculations are a hallmark symptom of diseases that affect the lower motor neurons, like ALS. Other lower motor neuron diseases that may cause fasciculations include post-polio syndrome, spinal muscular atrophy (SMA), and progressive muscular atrophy.

Besides neurological diseases, fasciculations may also be a symptom of certain diseases and conditions outside the nervous system, such as:

• An overactive thyroid gland
• An overactive or underactive parathyroid gland
• Electrolyte abnormalities (e.g., low phosphate levels or high calcium levels)
• Severe kidney disease
• Nutritional deficiencies, such as vitamin D, vitamin B12, magnesium, and potassium
  

Is Muscle Twitching a Sign of ALS?

Muscle twitching is a common symptom of ALS. The twitching is not painful, but it can interfere with sleep.

Fasciculations caused by ALS will be accompanied by other early symptoms:

• Weak or soft muscles
• Muscle cramping
• Symptoms affecting only one body region, or mild symptoms affecting more than one region
• Fatigue
• Poor balance
• Slurred words
• Weak grip
• Tripping when walking
• Tongue twitching

While ALS can occur at any age, people are most often affected in late middle age.

When to See a Healthcare Provider

If your muscle twitching is constant or has been recurring for a few months, or you have additional symptoms, check with your healthcare provider for an evaluation. Muscle twitching alone doesn't indicate ALS. Progressive muscle weakness is the hallmark symptom.

Other Causes of Twitch-Like Symptoms

Twitching is not the only sign of abnormal firing of neurons. Spasticity and clonus can easily be perceived as twitching, but medically, they're something different.

Spasticity

Spasticity describes muscle tightness and stiffness, as well as spasms that can be constant or sudden; some people describe these as a twitch.

Spasticityis a common symptom in MS and often affects one or both of the legs. It results from disrupted signals between the upper motor neurons and the lower motor neurons. In other words, there is impaired nerve transmission from the brain and spinal cord to the nerves that control your muscles.

Other conditions that may cause spasticity include:

• Adrenoleukodystrophy (ALD)
• Amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease)
• Brain damage
• Cerebral palsy
• Encephalitis
• Meningitis
• Phenylketonuria (PKU disease)
• Spinal cord injury
• Stroke
• Traumatic brain injury

Clonus

Clonus describes the repetitive jerking or twitching of muscles and, like spasticity, is thought to be caused by the faulty nerve transmission characteristic of MS. For example, the normal ankle jerk reflex is instead hyperactive and the muscle that controls the ankle shakes rhythmically and uncontrollably.

In more severe cases, the knee-jerk reflex is hyperactive and the muscle that controls the knee shakes rhythmically and uncontrollably.

Other causes of clonus include:

• Amyotrophic lateral sclerosis (ALS)
• Brain tumor
• Cerebral palsy
• Hereditary spastic paraparesis
• Infections, such as meningitis or encephalitis
• Kidney failure
• Liver failure
• Major injuries to the nerves in the brain or spinal cord
• Stroke

Is Twitching a Sign of MS?

Twitch-like spasticity and clonus are common muscle symptoms of MS. They're not quite the same as muscle twitching defined as fasciculations.

The difference between clonus and fasciculations is that clonus causes shock-like movements large enough to move a joint and fasciculations cause visible twitching in an individual muscle, but it's not enough to cause joint movement.

An MS muscle spasm might feel like a tight muscle or a painful contraction of the muscle. It could make it difficult to bend or straighten your leg, for example.

Diagnosis

Every disease and condition has its own set of established or widely accepted criteria for diagnosis.

To determine the underlying cause of your muscle twitching, your healthcare provider will likely do a physical examination and ask you questions such as:

• When your muscles began twitching
• Where the twitches occur
• How often the twitches occur
• How long the twitches last
• If you're having any other symptoms

If the healthcare provider suspects your muscle twitching may be due to an underlying condition, they may order blood tests, a magnetic resonance imaging (MRI) scan, a computed tomography (CT) scan, or electromyogramto assess the health of your muscles and the nerve cells that control them.

How Can I Stop Muscle Twitching?

Treating the underlying cause of muscle twitches is the primary concern, and it may stop the twitching. What that entails, of course, depends on what condition is at the root of the symptom.

If you are starting to notice muscle twitches (fasciculations), you can try the following tips to stop them:

• Get enough sleep
• Avoid caffeine
• Find ways to relax and destress
• Eat nutritious foods

Generally, speaking, medications that may be used to specifically address spasticity and clonus include:

• Neuromuscular blockers
• Muscle relaxants
• Benzodiazepines
  

Summary

Muscle twitching can have a number of different causes. Common causes are often benign, meaning the twitching is not due to an underlying disease or abnormality. In rare cases, muscle twitching can be a sign of a more serious medical condition, like ALS or MS.

By itself, muscle twitching need not be a cause for alarm. It may go away after a short while or with lifestyle modifications. If muscle twitches don't disappear on their own or are accompanied by muscle weakness, pain, or other abnormal symptoms, contact a healthcare provider. Your provider can help nail down the cause of muscle twitching and get you the treatment you need.