Potential Causes of Involuntary Movements

Involuntary movements refer to body movements outside of your control. These movements may be mild, such as a slight eye twitch, or quite pronounced and affect movements of the arms, trunk, or neck. Involuntary movements may be caused by chronic conditions, nerve damage, drug reactions, or brain injury.

Involuntary movements may be reversible, such as ones caused by a medication side effect, or permanent. Working with a neurologist, a doctor who specializes in brain disorders, will help you determine what is causing your involuntary movements, as well as how to treat them. 

Types

There are several types of involuntary movements that our bodies can make.

Tremors

Tremors are involuntary shaking in the hands, head, or other parts of the body. They worsen when you attempt basic movements. About 5 million people in the United States are affected by tremors.

Essential tremors are tremors that do not have a known cause. It’s estimated that about 50% of people with tremors have a family history of it. A tremor may be caused by:

• Multiple sclerosis
• Stroke
• Traumatic brain injury
• Parkinson’s disease
• Medication side effects
• Alcohol abuse
• Mercury poisoning
• Overactive thyroid
• Liver or kidney failure
• Anxiety 

Myoclonus

Myoclonus refers to fast jerks or twitches in a muscle or group of muscles. Myoclonus is considered a clinical sign and not a disease. Myoclonus is usually the result of dysfunction in the cerebral cortex part of the brain or the brainstem. 

When these jerky muscle movements affect one muscle or group of muscles, they are known as focal myoclonus. Jerky muscle movements that affect several muscle groups are known as multifocal myoclonus.

There are several different types of myoclonus. The most common type, cortical myoclonus, is caused by an irregularity in the sensorimotor cortex part of the brain.

There are a number of chronic conditions that can lead to myoclonus. They include:

• Celiac disease
• Angelman syndrome
• Huntington’s disease
• Rett syndrome
• Alzheimer’s disease
• Creutzfeldt-Jakob disease 

Tardive Dyskinesia

Tardive dyskinesia (TD) occurs as a result of taking antipsychotic drugs over a long period of time. It is characterized by repetitive involuntary movements like grimacing or eye blinking. These movements are often mild and can be reversed by stopping the medication.

However, it is possible to experience chronic or permanent tardive dyskinesia. Older people are more at risk than younger people of experiencing chronic TD. 

Tics

Tics are quick, repetitive movements or unwanted sounds. They are usually associated with Tourette syndrome, a hereditary neurological condition. Tics may also be associated with attention deficit hyperactivity disorder (ADHD), anxiety, depression, and obsessive-compulsive disorder (OCD). The first symptoms are usually involuntary movements of the face, arms, and legs that occur frequently.

Verbal tics may occur later on in Tourette syndrome, and can include grunting, shouting, throat clearing, or barking. A person experiencing verbal tics sometimes uses obscene words or gestures. This can make socialization quite difficult for a young person. 

Tics are usually present between the ages of 6 and 15. In most cases, they resolve by a person's early 20s. 

Athetosis

Athetosis describes slow, writhing movements, and usually affects the arms and hands. A person experiencing athetosis often puts their body into uncomfortable, twisted motions involuntarily.

It can begin at any age and often does not improve on its own. Athetosis is usually associated with chronic conditions like cerebral palsy, Huntington’s disease, and Wilson’s disease. It is caused by an irregularity in the basal ganglia part of the brain. 

Twitches

Muscle twitches occur when the muscles unexpectedly tighten or relax. Twitches are very common, and just about every one of us has experienced them.

Mild forms of twitches include having hiccups or jumping when you are startled. Twitches can also occur during exercise, thinking about exercise, falling asleep, or being sensitive to outside stimuli.

However, it is possible for twitches to have an underlying medical cause such as epilepsy or Parkinson’s disease. 

Causes

There are several possible causes of involuntary movements. Some causes may be temporary while others are chronic or permanent:

• Nervous system diseases 
• Medication side effect 
• Stroke
• Brain injury 
• Tumor
• Head or neck trauma 
• Genetic disorder
• Too much bilirubin (a yellow substance produced by the liver) in the blood
• Lack of oxygen (hypoxia)
• Illicit drugs 

Many involuntary muscle movements have several possible causes. For example, myoclonus may be caused by low levels of oxygen in the brain (hypoxia) or a metabolic process like kidney or liver failure. Spinal myoclonus can be caused by multiple sclerosis, syringomyelia, ischemic myelopathy, trauma to the spine, or infection.

Diagnosis

It’s important to see your doctor if you are experiencing any involuntary movements, no matter how small. Your primary doctor may refer you to a specialist such as a neurologist or a neurosurgeon.

Your medical team will order tests to determine the underlying cause of your involuntary movements, including:

• Blood tests
• Computed tomography (CT) scan of the head or affected body parts
• Magnetic resonance imaging (MRI) of the head or affected body parts
• Electroencephalogram (EEG)
• Lumbar puncture 
• Urinalysis 

The diagnostic process usually begins with a thorough history and physical exam. Some questions your doctor may ask include:

• When did the movements start?
• Did they come on suddenly or slowly?
• Are the movements present all the time or do they come and go?
• Has your posture been affected?
• Which body parts are affected by the movements?
• Have they been getting worse?
• Have you noticed any activities, such as exercise, that make the movements worse?
• Do you notice them more when you are stressed?
• Have you started any new medications lately?
• Do involuntary movements run in your family?
• Does anything improve them?
• Are you experiencing any other symptoms?

Treatment

Treatment for involuntary movements depends on the cause. Involuntary movements may be treated with medications, surgery, deep brain stimulation, or behavioral therapy. 

Your doctor may recommend meeting with a physical therapist to work on stretching and strengthening any muscles affected by involuntary movements. Exercises your physical therapist may recommend include swimming, walking, stretching, and balance exercises.

These exercises can help slow the damage done by involuntary movements, as well as promote coordination. This is especially helpful if you have become more prone to falls due to your involuntary movements.

Some cases of involuntary movements do not have a cure. Tardive dyskinesia, for example, is caused by a medication side effect. The only treatment is switching to a new class of antipsychotic drugs. This often helps reverse the condition, but is not always effective. 

Tremors

Your doctor may recommend the following treatment options:

• Anti-seizure medications
• Benzodiazepines 
• Beta-blockers
• Carbonic anhydrase inhibitors 
• Botox injections 
• Surgery
• Deep brain stimulation 

Myoclonus

Your doctor may recommend the following treatment options:

• Barbiturates 
• Phenytoin
• Primidone
• Sodium valproate
• Clonazepam 

Tics

Your doctor may recommend the following treatment options:

• Medications that block dopamine
• Stimulant medications
• Antidepressants 
• Behavioral therapy 

Twitches

Your doctor may recommend the following treatment options:

• Clonazepam
• Botox injections
• Avoiding stimuli 

Outlook

The prognosis for involuntary movements can vary widely depending on the cause and how severe the movements are. 

Some, such as tics, usually resolve on their own during a person's 20s. Others are chronic and require ongoing treatment. Talk with your neurologist about what is causing your involuntary movements and how to treat them. 

Summary

A wide range of conditions can cause involuntary movements. They may be uncomfortable and some may be chronic, but there are treatment options that can help in many cases. If you experience any involuntary movements, it's best to talk to your doctor so they can evaluate your symptoms and help you determine your next steps.