Nystagmus is a condition that causes involuntary, repetitive eye movements. These movements are usually side to side, but they can also be up and down or circular. Nystagmus can affect one or both eyes, and it can make it hard to see clearly or focus. This article explains the types, causes, symptoms, and treatment options available to Canadians living with this condition.
What Is Nystagmus?
Nystagmus refers to uncontrolled eye movements that a person cannot stop on their own. The word comes from the Greek word for “nodding.” Most people with nystagmus are not even aware their eyes are moving.
These eye movements happen in a rhythmic pattern. They may be slow in one direction and fast in the other, or they may move at the same speed in both directions. The movements are usually small, but they can affect vision and balance.
Nystagmus is not a disease on its own. Instead, it is often a sign of another condition affecting the eyes, the brain, or the inner ear. Learn more about nystagmus from the Mayo Clinic.
Types of Nystagmus: Physiological vs. Pathological
Doctors divide nystagmus into two broad categories: physiological (normal) and pathological (abnormal). Understanding the difference helps guide diagnosis and treatment.
Physiological Nystagmus
Physiological nystagmus is a normal response to certain situations. It does not mean anything is wrong with the eyes or brain. There are two common examples.
The first is optokinetic nystagmus, sometimes called “railway nystagmus.” This happens when your eyes try to follow a series of moving images — for example, watching trees pass by from a car window. Your eyes follow an image, then quickly snap back to find the next one.
The second is vestibular nystagmus. This type is triggered by stimulation of the inner ear. For example, spinning in a chair or having cool or warm water placed in the ear canal can trigger this response. It is the same sensation many people feel after spinning around quickly.
Pathological Nystagmus
Pathological nystagmus is the type that signals a medical concern. It can be present from birth (congenital) or it can develop later in life (acquired). Both types require proper medical assessment.
Congenital Nystagmus: Present From Birth or Early Childhood
Congenital nystagmus appears at birth or within the first few months of life. In some cases, the movements become less noticeable as the child grows older. However, they rarely disappear completely without treatment.
Congenital nystagmus can occur alongside other eye conditions. These include cataracts (clouding of the lens that can cause partial or complete vision loss), albinism (a lack of pigment affecting the eyes and skin), and strabismus (misaligned or “crossed” eyes). It may also appear with very small lesions on the retina, which is the light-sensitive tissue at the back of the eye.
In addition, some neurological conditions in newborns can cause congenital nystagmus. These include hydrocephalus (fluid build-up in the brain) and cerebral toxoplasmosis (a brain infection). However, congenital nystagmus sometimes appears with no clear cause at all. In these cases, it may run in families.
Jerk Nystagmus
The most common form of congenital nystagmus is called jerk nystagmus. The eyes move slowly in one horizontal direction, then snap back quickly in the opposite direction. This “slow-then-fast” pattern is what gives this type its name.
Pendular Nystagmus
Another form is pendular nystagmus. In this type, the eyes swing back and forth in a regular rhythm, like a pendulum on a clock. The movements are equal in speed in both directions.
How Congenital Nystagmus Affects Children
Children with congenital nystagmus often find that the movements get worse when they are tired, emotional, or concentrating hard — for example, while reading. Interestingly, children can sometimes reduce their own eye movements by turning their head to one side.
This head-turning behaviour, while helpful in the short term, can lead to torticollis — a stiff or twisted neck — if it continues over time. This is one reason early treatment is so important.
Acquired Nystagmus: Developing Later in Life
Acquired nystagmus develops in adolescence or adulthood. Unlike the congenital type, acquired nystagmus is almost always a sign of an underlying medical condition. It should always be investigated promptly.
Common causes of acquired nystagmus include:
Multiple sclerosis (MS) — a neurological condition that affects the brain and spinal cord
Brain tumours — whether in the brain itself or affecting the vestibular (balance) system
Cerebellar damage — injury to the cerebellum, the part of the brain that controls coordination and balance
Inner ear disorders — conditions that affect hearing and balance at the same time
Certain medications or substances — including some anti-seizure drugs or alcohol intoxication
Acquired nystagmus often comes with other symptoms. These may include dizziness, hearing changes, or problems with coordination. If you or someone you know suddenly develops nystagmus, seek medical attention right away.
Read Healthline’s overview of nystagmus types and causes for more detailed information.
How Is Nystagmus Diagnosed?
Diagnosing nystagmus involves both eye exams and neurological tests. The goal is not just to confirm the nystagmus, but to find out what is causing it.
Electronystagmography (ENG)
One of the key diagnostic tools is electronystagmography (ENG). This test records the electrical activity of eye movements using small electrodes placed near the eyes. It helps doctors identify the specific pattern of nystagmus and understand what type they are dealing with.
ENG is painless and non-invasive. It gives a detailed picture of how the eyes are moving and can point to problems in the vestibular system or the brain.
Other Assessments
Your doctor may also recommend additional tests. These can include an MRI or CT scan of the brain, a hearing evaluation, or blood tests. The specific tests depend on your age, medical history, and the type of nystagmus present.
In Canada, your family doctor can order initial testing and refer you to an ophthalmologist (eye specialist) or neurologist (brain and nerve specialist) as needed. Most provincial health plans cover these referrals.
Treatment Options for Nystagmus
Treatment for nystagmus depends on the type and the underlying cause. There is currently no single cure for nystagmus, but several options can improve vision and quality of life.
Corrective Lenses With Prisms
For children with congenital nystagmus who turn their heads to see better, prismatic lenses can make a significant difference. Prisms are special optical elements added to eyeglasses. They shift the image so that the eyes naturally move to the position where the nystagmus is least active.
This eliminates the need for the child to turn their head. Prismatic lenses can be temporary (stick-on) or permanent (built into the lens). When this treatment works well, it can correct abnormal head posture and reduce the risk of torticollis.
Surgery
When prismatic lenses are effective, surgery may be the next step. Surgical treatment repositions the eye muscles to shift the “null point” — the position where the eye is most stable — to straight ahead. The specific procedure depends on the type of nystagmus and its cause.
Surgery does not cure nystagmus completely. However, it can significantly reduce abnormal head posture and, in some cases, improve visual acuity. Your specialist will discuss whether surgery is appropriate for your situation.
Treating the Underlying Cause
For acquired nystagmus, treating the root cause is the main approach. For example, if nystagmus is caused by a vitamin deficiency or a medication, addressing that issue may resolve the eye movements. If MS or a tumour is the cause, treatment for that condition often reduces nystagmus as well.
In some cases, medications can help reduce the intensity of nystagmus. These are prescribed by a specialist and are not a first-line treatment for most people.
Visit Health Canada for information on accessing specialist care across Canada.
When to See a Doctor
If you notice that your child’s eyes seem to move on their own, speak with your family doctor as soon as possible. Early diagnosis leads to better outcomes. Most provinces offer referrals to paediatric ophthalmologists through your family doctor or a walk-in clinic.
For adults, sudden onset of nystagmus is a medical emergency. If you or someone you know suddenly develops uncontrolled eye movements — especially with dizziness, headache, or vision changes — go to the emergency department or call 911 immediately. Do not wait for a regular appointment in this case.
Even if symptoms seem mild, a visit to a walk-in clinic or your family doctor is a good first step. They can assess your symptoms, arrange appropriate tests, and refer you to the right specialist under your provincial health plan. Always consult a healthcare professional before drawing conclusions about eye movement symptoms.
Frequently Asked Questions About Nystagmus
Can nystagmus go away on its own?
In some cases, congenital nystagmus may become less noticeable as a child grows older. However, nystagmus rarely disappears completely without treatment. Acquired nystagmus may resolve if the underlying cause is successfully treated.
Is nystagmus a sign of a serious condition?
Nystagmus is not always serious, but it should always be evaluated by a doctor. Congenital nystagmus is often linked to other eye conditions rather than life-threatening illness. However, acquired nystagmus in adults can signal neurological conditions such as multiple sclerosis or a brain tumour, so prompt assessment is important.
Can a person with nystagmus drive a car?
Whether someone with nystagmus can drive depends on how much their vision is affected. Some people with mild nystagmus meet the legal vision standards required for a driver’s licence in Canada. An eye specialist can assess your visual acuity and advise you based on your province’s driving regulations.
What does nystagmus look like from the outside?
To an observer, nystagmus looks like rapid, rhythmic eye movements that the person cannot control. The eyes may move side to side, up and down, or in a circular pattern. The movements are usually small but can be visible, especially when the person is tired or concentrating.
Is nystagmus hereditary?
Some forms of congenital nystagmus do run in families, suggesting a genetic component. However, nystagmus can also occur with no family history at all. If you have a family history of nystagmus or related eye conditions, speak with your doctor about whether genetic counselling may be helpful.
How is nystagmus treated in children in Canada?
In Canada, children with nystagmus are typically referred to a paediatric ophthalmologist through their family doctor. Treatment may include corrective lenses with prisms, patching for related conditions, or surgery in some cases. Provincial health plans generally cover these specialist referrals and assessments.
Key Takeaways
Nystagmus causes involuntary, rhythmic eye movements that the person cannot control.
It can be physiological (normal, triggered by movement) or pathological (a sign of an underlying condition).
Congenital nystagmus is present from birth and may be linked to eye conditions, neurological disorders, or genetics.
Acquired nystagmus develops later in life and is often a sign of a neurological problem that needs urgent investigation.
Diagnosis may include electronystagmography (ENG), MRI, or specialist referral through your family doctor.
Treatment options include prismatic lenses, surgery, and treating the root cause.
Sudden onset of nystagmus in an adult is a medical emergency — seek care immediately.
Always speak with your family doctor or a walk-in clinic if you have concerns about eye movement symptoms.
