Ataxia is a loss of voluntary muscle coordination caused by damage to the brain, spinal cord, or nerves. It is not a single disease but a symptom or group of disorders that disrupts your ability to control movements like walking, speaking, swallowing, and using your hands. The cerebellum, the part of your brain responsible for fine-tuning movement and balance, is almost always involved.
How Ataxia Affects the Body
The cerebellum acts like a quality-control center for movement. It takes signals from your eyes, muscles, and inner ear, then smooths out the timing and force of every action. When the cerebellum or the nerve pathways leading to it are damaged, movements become poorly timed and imprecise. Simple tasks that normally happen on autopilot suddenly require concentration and still come out clumsy.
The most recognizable signs include:
- Unsteady walking, often with feet set wide apart for balance
- Poor coordination in the arms and hands, making it hard to eat, write, or button a shirt
- Slurred or slow speech, sometimes mistaken for intoxication
- Involuntary eye movements that jump back and forth
- Trouble swallowing, which can become dangerous over time
These symptoms can appear suddenly, over hours or days, or build gradually over years. How they show up depends entirely on what’s causing the damage.
Hereditary Ataxia
Some forms of ataxia are inherited, passed down through faulty genes that cause progressive degeneration of the cerebellum or spinal cord. Two broad categories dominate: Friedreich’s ataxia and the spinocerebellar ataxias.
Friedreich’s Ataxia
Friedreich’s ataxia is the most common inherited form, accounting for roughly half of all hereditary ataxia cases. It affects approximately 1 in 29,000 people, with a carrier rate estimated at 1 in 60 to 1 in 90 among people of European descent. It results from a mutation in the FXN gene, where a short segment of DNA that normally repeats 5 to 33 times instead repeats 66 to over 1,000 times. This excessive repetition cripples the gene’s ability to produce a protein the body needs to protect nerve cells and the heart.
Most people develop symptoms between ages 5 and 15, though about 25 percent have an atypical form that begins after age 25. Beyond coordination problems, Friedreich’s ataxia often causes a thickening of the heart muscle, diabetes, scoliosis, and gradual loss of strength and sensation in the arms and legs. It is a systemic disease, not just a movement disorder.
Spinocerebellar Ataxias
The spinocerebellar ataxias (SCAs) are a family of dominantly inherited disorders, meaning you only need one copy of the faulty gene from one parent to develop the condition. There are over 40 recognized subtypes, each linked to a different genetic mutation. They tend to appear in adulthood and progress at varying speeds.
A large European study tracking over 500 patients with the four most common subtypes found meaningful differences in survival. The 10-year survival rate was 57% for SCA1, 74% for SCA2, 73% for SCA3, and 87% for SCA6. Across all subtypes, difficulty swallowing and more severe coordination impairment at diagnosis were consistently linked to shorter survival. SCA6 tends to progress the slowest and has the best long-term outlook.
Acquired Ataxia
Not all ataxia is inherited. Many cases develop from external damage to the cerebellum or nervous system. Chronic heavy alcohol use is one of the most common causes, gradually destroying cerebellar tissue over years. Vitamin deficiencies, particularly B12 and vitamin E, can also trigger ataxia because these nutrients are essential for maintaining healthy nerve function.
Stroke, tumors, and traumatic brain injuries can cause sudden-onset ataxia by directly damaging the cerebellum or cutting off its blood supply. Autoimmune conditions, where the immune system mistakenly attacks the cerebellum, are another recognized trigger. Certain medications, including some anti-seizure drugs and chemotherapy agents, can produce ataxia as a side effect, and the symptoms sometimes reverse once the medication is stopped. Viral infections occasionally cause a temporary form of ataxia, especially in children, that typically resolves on its own within weeks.
How Ataxia Is Diagnosed
Diagnosing ataxia involves piecing together your symptoms, medical history, family history, and the results of several tests. A neurologist will typically watch you walk, test your coordination with simple tasks like touching your nose with your finger, and assess your eye movements and reflexes.
Brain imaging, usually an MRI, can reveal shrinkage of the cerebellum or other structural damage. Blood tests help rule out vitamin deficiencies, thyroid problems, and infections. Genetic testing can confirm a hereditary form. Clinicians often use a standardized scoring tool called the Scale for the Assessment and Rating of Ataxia (SARA) to measure severity across multiple movement categories and track changes over time.
Treatment and Management
For most types of ataxia, treatment focuses on managing symptoms and preserving function rather than curing the underlying condition. Acquired ataxias sometimes improve or resolve entirely if the cause is addressed: correcting a vitamin deficiency, removing a tumor, or stopping a harmful medication.
Physical therapy is a cornerstone of management for progressive forms. Structured rehabilitation programs typically combine land-based and aquatic exercises tailored to the individual. One clinical model uses six weeks of intensive outpatient therapy followed by a six-month supported home exercise program designed to sustain the functional gains made during the intensive phase. The goal is to maintain balance, strengthen muscles that compensate for lost coordination, and keep you mobile and independent for as long as possible. Occupational therapy helps with daily tasks, and speech therapy can address swallowing and communication difficulties.
Assistive devices become important as the condition progresses. Weighted utensils can make eating easier, specialized computer tools help with writing, and walkers or wheelchairs provide safe mobility when balance deteriorates beyond what therapy can manage.
The First Approved Drug for Friedreich’s Ataxia
In a significant milestone, the FDA approved the first pharmaceutical treatment specifically for Friedreich’s ataxia: a drug called Skyclarys (omaveloxolone), taken as a daily oral capsule. In a 48-week clinical trial of 103 patients, those taking the drug performed better on a standardized measure of Friedreich’s ataxia severity compared to those on placebo. Patients who continued treatment for up to three years in an open-label extension maintained better scores compared to untreated patients tracked in a separate natural history study.
The drug does not reverse the disease, but it appears to slow the worsening of motor function. Common side effects include signs of liver stress, headache, nausea, abdominal pain, and fatigue. No equivalent drug has been approved for the spinocerebellar ataxias or other forms, though clinical trials are ongoing for several subtypes.
Living With Ataxia
The daily reality of ataxia varies enormously depending on the type and stage. Early on, you might notice you trip more often, your handwriting becomes messier, or people ask if you’ve been drinking. As it progresses, tasks you once did without thinking, like carrying a cup of coffee across a room, require planning and effort. Social situations can become stressful when speech is affected, since slurred words are easily misinterpreted.
Fatigue is a persistent and underappreciated part of the condition. Your body works harder to do things that used to be effortless, and that extra effort is exhausting. Many people with ataxia find that pacing activities throughout the day and prioritizing rest makes a meaningful difference. Support groups, both in-person and online, provide a space where the frustrations of living with a rare condition are understood without explanation.